diff --git a/Gemfile b/Gemfile
index 0e373cc1..921484e4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -34,6 +34,7 @@ gem 'omniauth-oauth', '~> 1.2' # OAuth 1.0
 gem 'omniauth-rails_csrf_protection', '~> 2.0' # OAuth CSRF compatibility
 gem 'pundit', '~> 2.5.2' # For roles managements
 gem 'rack-attack', '~> 6.8.0' # For throttling incoming request in authentication
+gem 'rails-i18n', '~> 8.0' # For internationalization [https://github.com/svenfuchs/rails-i18n]
 gem 'rondo_form', '~> 1.0' # For nested forms
 gem 'rqrcode', '~> 3.0' # For generating QR codes
 gem 'tzinfo-data', '~> 1', platforms: %i[windows jruby] # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
diff --git a/Gemfile.lock b/Gemfile.lock
index 30b129f6..ab484aba 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -321,6 +321,9 @@ GEM
     rails-html-sanitizer (1.7.1)
       loofah (~> 2.25, >= 2.25.2)
       nokogiri (>= 1.15.7, != 1.16.7, != 1.16.6, != 1.16.5, != 1.16.4, != 1.16.3, != 1.16.2, != 1.16.1, != 1.16.0.rc1, != 1.16.0)
+    rails-i18n (8.1.0)
+      i18n (>= 0.7, < 2)
+      railties (>= 8.0.0, < 9)
     railties (8.1.3.1)
       actionpack (= 8.1.3.1)
       activesupport (= 8.1.3.1)
@@ -478,6 +481,7 @@ DEPENDENCIES
   pundit (~> 2.5.2)
   rack-attack (~> 6.8.0)
   rails (~> 8.1.3.1)
+  rails-i18n (~> 8.0)
   rondo_form (~> 1.0)
   rqrcode (~> 3.0)
   rubocop (~> 1.84)
@@ -615,6 +619,7 @@ CHECKSUMS
   rails (8.1.3.1) sha256=ccd11a36bfc171bf9c66d585d14c0ece91c0c9dde840aae60c0118d6f5c9c52a
   rails-dom-testing (2.3.0) sha256=8acc7953a7b911ca44588bf08737bc16719f431a1cc3091a292bca7317925c1d
   rails-html-sanitizer (1.7.1) sha256=e797a7c9b01e567307e317c576b49ab4168017e63eea4dba9ce3cb587e2f22c2
+  rails-i18n (8.1.0) sha256=52d5fd6c0abef28d84223cc05647f6ae0fd552637a1ede92deee9545755b6cf3
   railties (8.1.3.1) sha256=2388a232579a00cefea4487de66c8553c3408c1300abdc6cf1799d86ffb04487
   rainbow (3.1.1) sha256=039491aa3a89f42efa1d6dec2fc4e62ede96eb6acd95e52f1ad581182b79bc6a
   rake (13.3.1) sha256=8c9e89d09f66a26a01264e7e3480ec0607f0c497a861ef16063604b1b08eb19c
diff --git a/app/components/shared/header_component.html.haml b/app/components/shared/header_component.html.haml
index e75f5788..9fe54d2f 100644
--- a/app/components/shared/header_component.html.haml
+++ b/app/components/shared/header_component.html.haml
@@ -1,12 +1,12 @@
 %header.gh-topbar
-  = link_to home_path, class: 'gh-topbar-logo', 'aria-label': 'Gamification Hub, start' do
+  = link_to home_path, class: 'gh-topbar-logo', 'aria-label': t('layouts.header.home') do
     = image_tag 'logo.png', alt: ''
     %span.gh-topbar-logo-word Gamification Hub
 
   - if group_chrome
     %button.gh-group-switcher{ type: 'button',
                     data: { action: 'menu#open', menu_id_param: 'gh-group-switcher' },
-                    'aria-label': "Grupa #{group_chrome.name}, zmień grupę" }
+                    'aria-label': t('layouts.header.switch_group', name: group_chrome.name) }
       = render 'layouts/group_thumb', story_group: group_chrome.story_group, size: nil
       %span.gh-group-switcher-name= group_chrome.name
       %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
@@ -17,21 +17,21 @@
     - purse = group_chrome.student_membership
     = link_to story_group_student_currency_transactions_path(group_chrome.story_group, purse),
       class: 'gh-balance-button',
-      title: "#{purse.current_currency} do wydania, #{purse.total_currency} zebrane łącznie",
-      'aria-label': "Masz #{purse.current_currency} do wydania, pokaż historię waluty" do
+      title: t('layouts.header.balance_title', balance: purse.current_currency, total: purse.total_currency),
+      'aria-label': t('layouts.header.balance_label', balance: purse.current_currency) do
       = render 'layouts/currency_token', story_group: group_chrome.story_group, size: 32
       %span
         %b= purse.current_currency
-        %small do wydania
+        %small= t('layouts.header.to_spend')
 
   = link_to new_join_path, class: 'gh-btn gh-btn--secondary gh-btn--small gh-topbar-join-link',
     data: { turbo_frame: 'modal' } do
     %i.fa-solid.fa-plus
-    %span Dołącz do grupy
+    %span= t('layouts.header.join')
 
   %button.gh-icon-button.gh-topbar-theme-toggle{ type: 'button',
                                   data: { action: 'theme#toggle' },
-                                  'aria-label': 'Przełącz motyw' }
+                                  'aria-label': t('layouts.theme.toggle') }
     %i.fa-solid.fa-moon.gh-theme-icon-moon
     %i.fa-solid.fa-sun.gh-theme-icon-sun
 
@@ -44,6 +44,6 @@
 
   %button.gh-avatar-button{ type: 'button',
                     data: { action: 'menu#open', menu_id_param: 'gh-account-menu' },
-                    'aria-label': "Konto: #{user.full_name}" }
+                    'aria-label': t('layouts.header.account', name: user.full_name) }
     %span.gh-avatar.gh-octagon-clip{ 'data-gh-h': helpers.gh_avatar_hue(user.full_name), 'aria-hidden': 'true' }
       = helpers.gh_initials(user.full_name)
diff --git a/app/components/shared/header_component.rb b/app/components/shared/header_component.rb
index c25d2d9b..69345a59 100644
--- a/app/components/shared/header_component.rb
+++ b/app/components/shared/header_component.rb
@@ -20,8 +20,8 @@ def unread_count
   end
 
   def bell_label
-    return 'Powiadomienia' if unread_count.zero?
+    return t('layouts.header.notifications') if unread_count.zero?
 
-    "Powiadomienia, #{unread_count} #{helpers.gh_plural(unread_count, 'nowe', 'nowe', 'nowych')}"
+    t('layouts.header.notifications_unread', count: unread_count)
   end
 end
diff --git a/app/components/shared/sidebar_component.html.haml b/app/components/shared/sidebar_component.html.haml
index 3b9fd3f7..08ac4d12 100644
--- a/app/components/shared/sidebar_component.html.haml
+++ b/app/components/shared/sidebar_component.html.haml
@@ -1,6 +1,6 @@
 %aside.gh-sidebar{ class: ('gh-sidebar--collapsed' if collapsed),
               data: { sidebar_target: 'sidebar' } }
-  %nav.gh-sidebar-nav.gh-sidebar-nav--primary{ 'aria-label': 'Główna' }
+  %nav.gh-sidebar-nav.gh-sidebar-nav--primary{ 'aria-label': t('layouts.sidebar.main') }
     - nav_items.each do |item|
       = link_to item.path, class: "gh-sidebar-link #{'gh-sidebar-link--active' if current?(item.path)}",
         title: item.label, 'aria-current': ('page' if current?(item.path)) do
@@ -10,7 +10,7 @@
   - if group_chrome
     = render 'layouts/deck', chrome: group_chrome, current_path: current_path
   - elsif groups.any?
-    %p.gh-sidebar-section-label Twoje grupy
+    %p.gh-sidebar-section-label= t('layouts.sidebar.your_groups')
     .gh-sidebar-group-list
       - groups.each do |story_group|
         = link_to story_group_path(story_group), class: 'gh-sidebar-group-list-item', title: story_group.name do
diff --git a/app/components/shared/sidebar_component.rb b/app/components/shared/sidebar_component.rb
index 189cd664..52885048 100644
--- a/app/components/shared/sidebar_component.rb
+++ b/app/components/shared/sidebar_component.rb
@@ -25,7 +25,7 @@ def groups
   end
 
   def role_label(story_group)
-    StoryGroupsListing::ROLE_LABELS[role_for(story_group)]
+    t("story_groups.listing.roles.#{role_for(story_group)}")
   end
 
   def role_for(story_group)
@@ -44,7 +44,7 @@ def current?(path)
   end
 
   def toggle_label
-    collapsed ? 'Rozwiń' : 'Zwiń panel'
+    collapsed ? t('layouts.sidebar.expand') : t('layouts.sidebar.collapse')
   end
 
   def toggle_icon
diff --git a/app/components/shared/tab_bar_component.html.haml b/app/components/shared/tab_bar_component.html.haml
index 7fb3437a..cfae9664 100644
--- a/app/components/shared/tab_bar_component.html.haml
+++ b/app/components/shared/tab_bar_component.html.haml
@@ -1,4 +1,4 @@
-%nav.gh-mobile-tabbar{ 'aria-label': 'Nawigacja' }
+%nav.gh-mobile-tabbar{ 'aria-label': t('layouts.tab_bar.label') }
   - items.each do |item|
     - on = item.current?(current_path)
     = link_to item.path, class: "gh-mobile-tab #{'gh-mobile-tab--active' if on}",
@@ -10,4 +10,4 @@
   %button.gh-mobile-tab{ type: 'button',
                   data: { action: 'menu#open', menu_id_param: 'gh-more-sheet' } }
     %i.fa-solid.fa-ellipsis
-    %span Więcej
+    %span= t('shared.actions.more')
diff --git a/app/controllers/account_setups_controller.rb b/app/controllers/account_setups_controller.rb
index 3f5d9677..3d0fffd1 100644
--- a/app/controllers/account_setups_controller.rb
+++ b/app/controllers/account_setups_controller.rb
@@ -12,7 +12,7 @@ def update
     @current_user.first_login = false
 
     if @current_user.save(context: :account_setup)
-      redirect_to home_path, notice: 'Pomyślnie skonfigurowano konto.'
+      redirect_to home_path, notice: t('account_setups.flash.done')
     else
       @current_user.first_login = true
       render :edit, status: :unprocessable_content
diff --git a/app/controllers/activity_group_templates_controller.rb b/app/controllers/activity_group_templates_controller.rb
index c426c45c..c58e6997 100644
--- a/app/controllers/activity_group_templates_controller.rb
+++ b/app/controllers/activity_group_templates_controller.rb
@@ -11,7 +11,9 @@ class ActivityGroupTemplatesController < ApplicationController
   def new
     @activity_group_template = @story_group.activity_group_templates.build
 
-    @activity_group_template.categories.build(didactic_description: 'Obecność', reward: 2, position: 0)
+    @activity_group_template.categories.build(didactic_description: t('activity_group_templates.default_category'),
+                                              reward:               2,
+                                              position:             0,)
     @activity_group_template.categories.build(reward: 1, position: 1)
   end
 
@@ -28,7 +30,8 @@ def create
 
     if @activity_group_template.save(context: :settings)
       redirect_to story_group_activity_groups_path(@story_group),
-                  notice: "Utworzono szablon „#{@activity_group_template.base_name}”.", status: :see_other
+                  notice: t('activity_group_templates.flash.created', name: @activity_group_template.base_name),
+                  status: :see_other
     else
       render :new, status: :unprocessable_content
     end
@@ -39,7 +42,7 @@ def update
 
     if @activity_group_template.save(context: :settings)
       redirect_to story_group_activity_groups_path(@story_group),
-                  notice: 'Zapisano szablon. Nowe arkusze dostaną te kategorie.', status: :see_other
+                  notice: t('activity_group_templates.flash.updated'), status: :see_other
     else
       @sheet_names = sheet_names_for(@activity_group_template)
       render :edit, status: :unprocessable_content
@@ -51,7 +54,7 @@ def destroy
     @activity_group_template.soft_delete!
 
     redirect_outside_turbo_frame story_group_activity_groups_path(@story_group),
-                                 notice: "Usunięto szablon „#{name}”. Utworzone z niego arkusze zostają."
+                                 notice: t('activity_group_templates.flash.destroyed', name: name)
   end
 
   private
diff --git a/app/controllers/activity_groups_controller.rb b/app/controllers/activity_groups_controller.rb
index 5d6f34f2..91f642cb 100644
--- a/app/controllers/activity_groups_controller.rb
+++ b/app/controllers/activity_groups_controller.rb
@@ -43,7 +43,7 @@ def update
 
     if @activity_group.save(context: :settings)
       redirect_to story_group_activity_groups_path(@story_group),
-                  notice: "Zapisano ustawienia arkusza #{@activity_group.name}.", status: :see_other
+                  notice: t('activity_groups.flash.updated', name: @activity_group.name), status: :see_other
     else
       render :edit, status: :unprocessable_content
     end
@@ -54,8 +54,7 @@ def destroy
     @activity_group.soft_delete!
 
     redirect_outside_turbo_frame story_group_activity_groups_path(@story_group),
-                                 notice: "Usunięto arkusz #{name}. " \
-                                         'Przyznane nagrody zostają w historii studentów.'
+                                 notice: t('activity_groups.flash.destroyed', name: name)
   end
 
   private
@@ -87,9 +86,9 @@ def bulk_count
   end
 
   def created_notice(sheets)
-    return "Utworzono: #{sheets.first.name}." if sheets.one?
+    return t('activity_groups.flash.created_one', name: sheets.first.name) if sheets.one?
 
-    "Utworzono: #{sheets.first.name} – #{sheets.last.name}."
+    t('activity_groups.flash.created_many', first: sheets.first.name, last: sheets.last.name)
   end
 
   def columns_changed?
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 0e24dbc7..6406ac23 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -2,6 +2,7 @@
 
 class ApplicationController < ActionController::Base
   include Pundit::Authorization
+  include Localization
   include Authentication
   include Sidebar
   include StatusRedirects
diff --git a/app/controllers/auth/passwordless_controller.rb b/app/controllers/auth/passwordless_controller.rb
index e29ed773..482e48ea 100644
--- a/app/controllers/auth/passwordless_controller.rb
+++ b/app/controllers/auth/passwordless_controller.rb
@@ -30,7 +30,7 @@ def verify
     token = params.expect(:token)
     login_token = LoginToken.find_by_token(token)
 
-    return redirect_to login_path, alert: 'Nieprawidłowy token' if login_token.nil? || login_token.expired?
+    return redirect_to login_path, alert: t('auth.flash.invalid_token') if login_token.nil? || login_token.expired?
 
     user = login_token.user
     user.consume_login_token!
@@ -61,7 +61,7 @@ def create
     session[:pending_login_email]   = email
     session[:pending_login_sent_at] = Time.current.to_i
 
-    notice = 'Wysłaliśmy nowy link. Poprzedni już nie działa.' if resend
+    notice = t('auth.flash.resent') if resend
     redirect_to auth_passwordless_inbox_path, notice: notice
   end
 
diff --git a/app/controllers/auth/usos_controller.rb b/app/controllers/auth/usos_controller.rb
index 474d8ac9..6536820b 100644
--- a/app/controllers/auth/usos_controller.rb
+++ b/app/controllers/auth/usos_controller.rb
@@ -16,9 +16,9 @@ def create
 
     sign_in_and_redirect(user)
   rescue InvalidProviderError
-    redirect_to root_path, alert: 'Nieprawidłowy dostawca logowania.'
+    redirect_to root_path, alert: t('auth.flash.invalid_provider')
   rescue Providers::InvalidAuthError
-    redirect_to root_path, alert: 'Nieprawidłowa próba autoryzacji.'
+    redirect_to root_path, alert: t('auth.flash.invalid_auth')
   end
 
   private
diff --git a/app/controllers/badges_controller.rb b/app/controllers/badges_controller.rb
index f02ab869..6ecd0760 100644
--- a/app/controllers/badges_controller.rb
+++ b/app/controllers/badges_controller.rb
@@ -32,7 +32,7 @@ def create
     @badge = @story_group.badges.build(badge_params)
 
     if @badge.save
-      redirect_to story_group_badges_path(@story_group), notice: "Dodano odznakę „#{@badge.name}”."
+      redirect_to story_group_badges_path(@story_group), notice: t('badges.flash.created', name: @badge.name)
     else
       set_shelf
       render :new, status: :unprocessable_content
@@ -41,7 +41,7 @@ def create
 
   def update
     if @badge.update(badge_params)
-      redirect_to story_group_badges_path(@story_group), notice: "Zapisano odznakę „#{@badge.name}”."
+      redirect_to story_group_badges_path(@story_group), notice: t('badges.flash.updated', name: @badge.name)
     else
       set_shelf
       render :edit, status: :unprocessable_content
@@ -53,8 +53,7 @@ def destroy
     @badge.soft_delete!
 
     redirect_outside_turbo_frame story_group_badges_path(@story_group),
-                                 notice: "Usunięto odznakę „#{name}”. Studenci, " \
-                                         'którzy ją mają, zachowują ją w historii.'
+                                 notice: t('badges.flash.destroyed', name: name)
   end
 
   private
diff --git a/app/controllers/concerns/auth/sign_in.rb b/app/controllers/concerns/auth/sign_in.rb
index 907f2b0e..4b8164a3 100644
--- a/app/controllers/concerns/auth/sign_in.rb
+++ b/app/controllers/concerns/auth/sign_in.rb
@@ -10,7 +10,7 @@ def sign_in_and_redirect(user)
     reset_session
     session[:user_id] = user.id
 
-    redirect_to after_login_path(return_to), notice: 'Zalogowano pomyślnie.'
+    redirect_to after_login_path(return_to), notice: t('auth.flash.signed_in')
   end
 
   def after_login_path(path)
diff --git a/app/controllers/concerns/authentication.rb b/app/controllers/concerns/authentication.rb
index d41faabe..e35fb53b 100644
--- a/app/controllers/concerns/authentication.rb
+++ b/app/controllers/concerns/authentication.rb
@@ -21,7 +21,7 @@ def authenticate!
     return if @current_user
 
     store_return_path
-    redirect_to login_path, alert: 'Zaloguj się, aby kontynuować.'
+    redirect_to login_path, alert: t('application.flash.log_in_first')
   end
 
   def store_return_path
diff --git a/app/controllers/concerns/localization.rb b/app/controllers/concerns/localization.rb
new file mode 100644
index 00000000..8d3d38f0
--- /dev/null
+++ b/app/controllers/concerns/localization.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+module Localization
+  extend ActiveSupport::Concern
+
+  LOCALE_COOKIE = :locale
+
+  included do
+    around_action :switch_locale
+  end
+
+  protected
+
+  # A block keeps the locale from leaking into the next request served by the same thread.
+  def switch_locale(&)
+    I18n.with_locale(requested_locale, &)
+  end
+
+  def requested_locale
+    [cookies[LOCALE_COOKIE], browser_locale].find { |locale| available_locale?(locale) } || I18n.default_locale
+  end
+
+  # "en-US,en;q=0.9,pl;q=0.8" -> "en". Browsers list languages in order of preference.
+  def browser_locale
+    request.headers['Accept-Language'].to_s.split(',')
+           .map { |entry| entry.strip.first(2).downcase }
+           .find { |locale| available_locale?(locale) }
+  end
+
+  def available_locale?(locale)
+    I18n.available_locales.map(&:to_s).include?(locale.to_s)
+  end
+end
diff --git a/app/controllers/concerns/logged_user_redirector.rb b/app/controllers/concerns/logged_user_redirector.rb
index 434acf22..9dca80a1 100644
--- a/app/controllers/concerns/logged_user_redirector.rb
+++ b/app/controllers/concerns/logged_user_redirector.rb
@@ -2,6 +2,6 @@
 
 module LoggedUserRedirector
   def redirect_logged_user
-    redirect_to root_path, alert: 'Jesteś już zalogowany.' if @current_user
+    redirect_to root_path, alert: t('application.flash.already_signed_in') if @current_user
   end
 end
diff --git a/app/controllers/concerns/status_redirects.rb b/app/controllers/concerns/status_redirects.rb
index 69180f2c..a6543ffd 100644
--- a/app/controllers/concerns/status_redirects.rb
+++ b/app/controllers/concerns/status_redirects.rb
@@ -4,10 +4,10 @@ module StatusRedirects
   protected
 
   def record_not_found
-    redirect_to root_path, alert: 'Nie znaleziono.'
+    redirect_to root_path, alert: t('application.flash.not_found')
   end
 
   def not_authorized
-    redirect_to root_path, alert: 'Nie znaleziono.'
+    redirect_to root_path, alert: t('application.flash.not_found')
   end
 end
diff --git a/app/controllers/currency_adjustments_controller.rb b/app/controllers/currency_adjustments_controller.rb
index 69e60cfa..1fb30ee1 100644
--- a/app/controllers/currency_adjustments_controller.rb
+++ b/app/controllers/currency_adjustments_controller.rb
@@ -38,8 +38,8 @@ def set_presentation
   end
 
   def notice_for(form)
-    verb = form.positive? ? 'Dodano' : 'Odjęto'
+    key = form.positive? ? 'added' : 'taken'
 
-    "#{verb} #{form.value}. Saldo: #{@student.reload.current_currency}."
+    t("currency_adjustments.flash.#{key}", value: form.value, balance: @student.reload.current_currency)
   end
 end
diff --git a/app/controllers/currency_transactions_controller.rb b/app/controllers/currency_transactions_controller.rb
index 5ed2ac1c..f483a43e 100644
--- a/app/controllers/currency_transactions_controller.rb
+++ b/app/controllers/currency_transactions_controller.rb
@@ -31,7 +31,7 @@ def set_student
   end
 
   def ledger_kind
-    kinds = CurrencyLedger::KINDS.map(&:first).compact
+    kinds = CurrencyLedger::KINDS.compact
     kinds.include?(params[:kind]) ? params[:kind] : nil
   end
 end
diff --git a/app/controllers/items_controller.rb b/app/controllers/items_controller.rb
index 27a7f866..325a3e12 100644
--- a/app/controllers/items_controller.rb
+++ b/app/controllers/items_controller.rb
@@ -32,7 +32,7 @@ def create
 
     if @item.save
       redirect_to story_group_items_path(@story_group),
-                  notice: "Dodano przedmiot „#{@item.name}” do sklepu."
+                  notice: t('items.flash.created', name: @item.name)
     else
       set_shelf
       render :new, status: :unprocessable_content
@@ -42,7 +42,7 @@ def create
   def update
     if @item.update(item_params)
       redirect_to story_group_items_path(@story_group),
-                  notice: "Zapisano „#{@item.name}”. Zmiany dotyczą nowych zakupów."
+                  notice: t('items.flash.updated', name: @item.name)
     else
       set_shelf
       render :edit, status: :unprocessable_content
@@ -54,8 +54,7 @@ def destroy
     @item.soft_delete!
 
     redirect_outside_turbo_frame story_group_items_path(@story_group),
-                                 notice: "Usunięto „#{name}” z oferty. " \
-                                         'Kupione egzemplarze zostają u studentów.'
+                                 notice: t('items.flash.destroyed', name: name)
   end
 
   private
diff --git a/app/controllers/locales_controller.rb b/app/controllers/locales_controller.rb
new file mode 100644
index 00000000..f037647d
--- /dev/null
+++ b/app/controllers/locales_controller.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+class LocalesController < ApplicationController
+  skip_before_action :authenticate!
+
+  def update
+    locale = params[:locale].to_s
+    cookies.permanent[Localization::LOCALE_COOKIE] = locale if available_locale?(locale)
+
+    redirect_back_or_to root_path, status: :see_other
+  end
+end
diff --git a/app/controllers/organizations/admins_controller.rb b/app/controllers/organizations/admins_controller.rb
index 04265fa0..0eb48316 100644
--- a/app/controllers/organizations/admins_controller.rb
+++ b/app/controllers/organizations/admins_controller.rb
@@ -10,7 +10,7 @@ def confirm_destroy; end
   def destroy
     @admin.destroy!
 
-    redirect_after_destroy notice: "Usunięto administratora: #{display_name}."
+    redirect_after_destroy notice: t('organizations.flash.admin_removed', name: display_name)
   end
 
   private
diff --git a/app/controllers/organizations/invitations_controller.rb b/app/controllers/organizations/invitations_controller.rb
index de787bdd..5aaa0675 100644
--- a/app/controllers/organizations/invitations_controller.rb
+++ b/app/controllers/organizations/invitations_controller.rb
@@ -13,14 +13,14 @@ def create
     send_invitation(user, create_invitation_token(user))
 
     redirect_to organization_path(organization), status: :see_other,
-                                                 notice: "Wysłano ponownie zaproszenie: #{user.email}."
+                                                 notice: t('organizations.flash.invitation_resent', email: user.email)
   end
 
   private
 
   def too_many_resends
     redirect_to organization_path(params[:organization_id]),
-                alert:  'Zaproszenie zostało już wysłane kilka razy. Spróbuj ponownie za kilka minut.',
+                alert:  t('organizations.flash.too_many_resends'),
                 status: :see_other
   end
 end
diff --git a/app/controllers/organizations/users_controller.rb b/app/controllers/organizations/users_controller.rb
index 6c4da1c5..e2d5edb9 100644
--- a/app/controllers/organizations/users_controller.rb
+++ b/app/controllers/organizations/users_controller.rb
@@ -13,7 +13,7 @@ def update
     @user.assign_attributes(user_params)
 
     if @user.save(context: :user_invitation)
-      redirect_after_save notice: "Zapisano zmiany: #{@user.full_name}."
+      redirect_after_save notice: t('organizations.flash.user_updated', name: @user.full_name)
     else
       render :edit, status: :unprocessable_content
     end
@@ -25,7 +25,7 @@ def destroy
     name = @user.full_name
     @user.destroy!
 
-    redirect_after_save notice: "Usunięto użytkownika: #{name}."
+    redirect_after_save notice: t('organizations.flash.user_removed', name: name)
   end
 
   private
diff --git a/app/controllers/organizations_controller.rb b/app/controllers/organizations_controller.rb
index 09e57a53..be7c1698 100644
--- a/app/controllers/organizations_controller.rb
+++ b/app/controllers/organizations_controller.rb
@@ -37,7 +37,7 @@ def create
     authorize @organization
 
     if @organization.save
-      redirect_after_save organization_path(@organization), notice: 'Pomyślnie utworzono organizację.'
+      redirect_after_save organization_path(@organization), notice: t('organizations.flash.created')
     else
       render :new, status: :unprocessable_content
     end
@@ -51,7 +51,7 @@ def update
     authorize @organization
 
     if @organization.update(organization_params)
-      redirect_after_save organization_path(@organization), notice: 'Pomyślnie zaktualizowano organizację.'
+      redirect_after_save organization_path(@organization), notice: t('organizations.flash.updated')
     else
       render :edit, status: :unprocessable_content
     end
@@ -70,7 +70,7 @@ def destroy
     end
 
     @organization.destroy!
-    redirect_after_save organizations_path, notice: "Usunięto organizację #{@organization.name}."
+    redirect_after_save organizations_path, notice: t('organizations.flash.destroyed', name: @organization.name)
   end
 
   def new_admin
@@ -96,7 +96,7 @@ def add_admin
     if token
       send_invitation(@org_admin, token)
       redirect_after_save organization_path(@organization),
-                          notice: 'Pomyślnie dodano administratora organizacji. Wysłano zaproszenie na email.'
+                          notice: t('organizations.flash.admin_added')
     else
       render :new_admin, status: :unprocessable_content
     end
@@ -124,7 +124,7 @@ def add_user
     if token
       send_invitation(@new_user, token)
       redirect_after_save organization_path(@organization),
-                          notice: 'Pomyślnie dodano użytkownika do organizacji. Wysłano zaproszenie na email.'
+                          notice: t('organizations.flash.user_added')
     else
       render :new_user, status: :unprocessable_content
     end
diff --git a/app/controllers/ranking_controller.rb b/app/controllers/ranking_controller.rb
index cc43c075..85ad1297 100644
--- a/app/controllers/ranking_controller.rb
+++ b/app/controllers/ranking_controller.rb
@@ -46,10 +46,10 @@ def ranking_params
   end
 
   def notice_for_update
-    return 'Ranking ukryty przed studentami.' unless @story_group.ranking_enabled?
-    return 'Ranking widoczny w całości.' if @story_group.ranking_full?
+    return t('ranking.flash.hidden') unless @story_group.ranking_enabled?
+    return t('ranking.flash.full') if @story_group.ranking_full?
 
-    'Ranking widoczny: podium i własne miejsce.'
+    t('ranking.flash.podium')
   end
 
   def gh_group_chrome
diff --git a/app/controllers/ranks_controller.rb b/app/controllers/ranks_controller.rb
index 3c50c5fe..1f898c2d 100644
--- a/app/controllers/ranks_controller.rb
+++ b/app/controllers/ranks_controller.rb
@@ -33,7 +33,7 @@ def create
     @rank = @story_group.ranks.build(rank_params)
 
     if @rank.save
-      redirect_to story_group_ranks_path(@story_group), notice: "Dodano rangę „#{@rank.name}”."
+      redirect_to story_group_ranks_path(@story_group), notice: t('ranks.flash.created', name: @rank.name)
     else
       set_ladder
       render :new, status: :unprocessable_content
@@ -42,7 +42,7 @@ def create
 
   def update
     if @rank.update(rank_params)
-      redirect_to story_group_ranks_path(@story_group), notice: "Zapisano rangę „#{@rank.name}”."
+      redirect_to story_group_ranks_path(@story_group), notice: t('ranks.flash.updated', name: @rank.name)
     else
       set_ladder
       render :edit, status: :unprocessable_content
@@ -55,13 +55,13 @@ def destroy
 
     if blockers.any?
       return redirect_outside_turbo_frame story_group_ranks_path(@story_group),
-                                          alert: "Nie można usunąć rangi „#{name}”: wymagają jej " \
-                                                 "przedmioty #{helpers.gh_and_list(blockers)}."
+                                          alert: t('ranks.flash.blocked', name:  name,
+                                                                          items: helpers.gh_and_list(blockers),)
     end
 
     @rank.destroy
     redirect_outside_turbo_frame story_group_ranks_path(@story_group),
-                                 notice: "Usunięto rangę „#{name}”."
+                                 notice: t('ranks.flash.destroyed', name: name)
   end
 
   private
diff --git a/app/controllers/shop_controller.rb b/app/controllers/shop_controller.rb
index 47c51823..6373ba73 100644
--- a/app/controllers/shop_controller.rb
+++ b/app/controllers/shop_controller.rb
@@ -35,7 +35,7 @@ def confirm_buy
     return if shop.state_for(@item) == :afford
 
     redirect_to story_group_shop_index_path(@story_group),
-                alert: "Nie możesz teraz kupić „#{@item.name}”."
+                alert: t('shop.flash.unavailable', name: @item.name)
   end
 
   # POST /story_groups/:story_group_id/shop/:id/buy
@@ -44,7 +44,7 @@ def buy
 
     if result.success?
       redirect_to story_group_shop_index_path(@story_group),
-                  notice: "Kupione: „#{@item.name}”. Zostało Ci #{@student.current_currency}."
+                  notice: t('shop.flash.bought', name: @item.name, balance: @student.current_currency)
     else
       redirect_to story_group_shop_index_path(@story_group), alert: result.errors.join(', ')
     end
diff --git a/app/controllers/story_group_invites_controller.rb b/app/controllers/story_group_invites_controller.rb
index 877486c9..3f3bb794 100644
--- a/app/controllers/story_group_invites_controller.rb
+++ b/app/controllers/story_group_invites_controller.rb
@@ -38,8 +38,7 @@ def create
 
     flash[:fresh_invite] = @form.invite.id
     redirect_outside_turbo_frame story_group_invites_path(@story_group),
-                                 notice: "Utworzono kod #{@form.invite.code}. " \
-                                         'Kliknij „Pokaż”, żeby wyświetlić go studentom.'
+                                 notice: t('story_group_invites.flash.created', code: @form.invite.code)
   end
 
   def update
@@ -47,7 +46,7 @@ def update
     return render :edit, status: :unprocessable_content unless @form.save
 
     redirect_outside_turbo_frame story_group_invites_path(@story_group),
-                                 notice: "Zapisano zaproszenie #{@invite.code}."
+                                 notice: t('story_group_invites.flash.updated', code: @invite.code)
   end
 
   def destroy
@@ -55,7 +54,7 @@ def destroy
     @invite.destroy
 
     redirect_outside_turbo_frame story_group_invites_path(@story_group),
-                                 notice: "Usunięto zaproszenie #{code}."
+                                 notice: t('story_group_invites.flash.destroyed', code: code)
   end
 
   private
diff --git a/app/controllers/story_group_memberships_controller.rb b/app/controllers/story_group_memberships_controller.rb
index fff3f22a..3a79c1aa 100644
--- a/app/controllers/story_group_memberships_controller.rb
+++ b/app/controllers/story_group_memberships_controller.rb
@@ -23,7 +23,7 @@ def update
       return render(from_dialog? ? :nickname : :edit, status: :unprocessable_content)
     end
 
-    notice = "Twój pseudonim w tej grupie: #{@membership.display_name}."
+    notice = t('story_group_memberships.flash.nickname', name: @membership.display_name)
     return redirect_to(edit_story_group_membership_path(@story_group), notice: notice) unless from_dialog?
 
     redirect_outside_turbo_frame story_group_ranking_path(@story_group), notice: notice
@@ -39,7 +39,7 @@ def destroy
     name = @story_group.name
     @membership.destroy!
 
-    redirect_to story_groups_path, notice: "Opuszczono grupę #{name}.", status: :see_other
+    redirect_to story_groups_path, notice: t('story_group_memberships.flash.left', name: name), status: :see_other
   end
 
   private
diff --git a/app/controllers/story_groups_controller.rb b/app/controllers/story_groups_controller.rb
index 9531db41..662ba935 100644
--- a/app/controllers/story_groups_controller.rb
+++ b/app/controllers/story_groups_controller.rb
@@ -80,7 +80,7 @@ def update
     authorize @story_group
 
     if @story_group.update(story_group_params)
-      redirect_to edit_story_group_path(@story_group), notice: 'Zapisano ustawienia grupy.'
+      redirect_to edit_story_group_path(@story_group), notice: t('story_groups.flash.updated')
     else
       render :edit, status: :unprocessable_content
     end
@@ -100,7 +100,7 @@ def destroy
 
     name = @story_group.name
     @story_group.destroy!
-    notice = "Usunięto grupę #{name}."
+    notice = t('story_groups.flash.destroyed', name: name)
 
     return redirect_outside_turbo_frame(story_groups_path, notice: notice) if @in_modal
 
diff --git a/app/controllers/students_activity_group_categories_controller.rb b/app/controllers/students_activity_group_categories_controller.rb
index 9c7876ac..e934a6e6 100644
--- a/app/controllers/students_activity_group_categories_controller.rb
+++ b/app/controllers/students_activity_group_categories_controller.rb
@@ -41,10 +41,11 @@ def set_activity_group
   end
 
   def award_notice(result)
-    return 'Nie zaznaczono żadnego pola.' if result.pairs.none?
+    return t('students_activity_group_categories.flash.nothing') if result.pairs.none?
 
-    students = helpers.gh_plural(result.students, 'studentowi', 'studentom', 'studentom')
-    "Przyznano #{result.total} #{@story_group.currency_name} #{result.students} #{students}."
+    t('students_activity_group_categories.flash.awarded', total:    result.total,
+                                                          currency: @story_group.currency_name,
+                                                          count:    result.students,)
   end
 
   # `completions[student_id][category_id]`. A missing key is not a revocation —
diff --git a/app/controllers/students_badges_controller.rb b/app/controllers/students_badges_controller.rb
index 49943b10..8733837e 100644
--- a/app/controllers/students_badges_controller.rb
+++ b/app/controllers/students_badges_controller.rb
@@ -25,7 +25,7 @@ def create
 
     if saved
       redirect_outside_turbo_frame story_group_student_path(@story_group, @student),
-                                   notice: "Przyznano odznakę „#{@students_badge.name}”."
+                                   notice: t('students_badges.flash.awarded', name: @students_badge.name)
     else
       set_badges
       render :new, status: :unprocessable_content
@@ -37,7 +37,7 @@ def destroy
     @students_badge.destroy
 
     redirect_outside_turbo_frame story_group_student_path(@story_group, @student),
-                                 notice: "Odebrano odznakę „#{name}”."
+                                 notice: t('students_badges.flash.revoked', name: name)
   end
 
   private
diff --git a/app/controllers/students_controller.rb b/app/controllers/students_controller.rb
index 5f85c8b9..4ada507e 100644
--- a/app/controllers/students_controller.rb
+++ b/app/controllers/students_controller.rb
@@ -58,7 +58,7 @@ def update_lives
       redirect_to story_group_students_path(@story_group), notice: lives_notice
     else
       redirect_to story_group_students_path(@story_group),
-                  alert: 'Nie można odebrać życia — student ma już 0.'
+                  alert: t('students.flash.cannot_take_life')
     end
   end
 
@@ -71,7 +71,7 @@ def destroy
     # "Usunięto Anna Kowalska" would be the wrong case and there is no way to
     # decline a name here.
     redirect_outside_turbo_frame story_group_students_path(@story_group),
-                                 notice: "#{name} nie należy już do grupy."
+                                 notice: t('students.flash.removed', name: name)
   end
 
   private
@@ -97,7 +97,7 @@ def sheet
 
   # The ledger tab's filter, as a kind or nil for "Wszystkie".
   def ledger_kind
-    kinds = CurrencyLedger::KINDS.map(&:first).compact
+    kinds = CurrencyLedger::KINDS.compact
     kinds.include?(params[:kind]) ? params[:kind] : nil
   end
 
@@ -105,9 +105,7 @@ def ledger_kind
   # this form and this stepper can do, so the toast says the result rather than
   # "zapisano".
   def lives_notice
-    lives = @student.lives.to_i
-
-    "#{@student.display_name} ma teraz #{lives} #{helpers.gh_plural(lives, 'życie', 'życia', 'żyć')}."
+    t('students.flash.lives_notice', name: @student.display_name, count: @student.lives.to_i)
   end
 
   def update_student_params
diff --git a/app/controllers/teachers_controller.rb b/app/controllers/teachers_controller.rb
index c8d6b1bc..d9bb0e5f 100644
--- a/app/controllers/teachers_controller.rb
+++ b/app/controllers/teachers_controller.rb
@@ -26,7 +26,7 @@ def create
 
     if @teacher.save
       redirect_outside_turbo_frame story_group_teachers_path(@story_group),
-                                   notice: "Dodano: #{@teacher.full_name}."
+                                   notice: t('teachers.flash.added', name: @teacher.full_name)
     else
       set_pool
       render :new, status: :unprocessable_content
@@ -38,7 +38,7 @@ def destroy
     @teacher.destroy
 
     redirect_outside_turbo_frame story_group_teachers_path(@story_group),
-                                 notice: "Usunięto z grupy: #{name}."
+                                 notice: t('teachers.flash.removed', name: name)
   end
 
   private
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 12fc768b..86299c40 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -8,15 +8,21 @@ def transaction_description(transaction, story_group)
     student_name = transaction.student.full_name
     case transaction.kind
     when 'purchase'
-      item_name = transaction.transactionable&.name || 'przedmiot'
-      "#{student_name} zakupił #{item_name} za #{transaction.amount.abs} #{story_group.currency_name}"
+      item_name = transaction.transactionable&.name || t('application.helpers.transaction.item_fallback')
+      t('application.helpers.transaction.purchase', student:  student_name,
+                                                    item:     item_name,
+                                                    amount:   transaction.amount.abs,
+                                                    currency: story_group.currency_name,)
     when 'reward'
-      category_name = transaction.transactionable&.didactic_description || 'aktywność'
-      "#{student_name} zdobył nagrodę za: #{category_name}"
+      category_name = transaction.transactionable&.didactic_description ||
+                      t('application.helpers.transaction.category_fallback')
+      t('application.helpers.transaction.reward', student: student_name, category: category_name)
     when 'adjustment'
       sign = transaction.amount >= 0 ? '+' : ''
-      adjuster = transaction.granted_by_user&.full_name || 'nauczyciel'
-      "#{adjuster} skorygował walutę #{student_name} (#{sign}#{transaction.amount})"
+      adjuster = transaction.granted_by_user&.full_name || t('application.helpers.transaction.adjuster_fallback')
+      t('application.helpers.transaction.adjustment', adjuster: adjuster,
+                                                      student:  student_name,
+                                                      amount:   "#{sign}#{transaction.amount}",)
     end
   end
 
@@ -36,12 +42,8 @@ def gh_group_chrome
     @gh_group_chrome = GroupChrome.for(user: @current_user, story_group: @story_group)
   end
 
-  def gh_plural(count, one, few, many)
-    Plural.pick(count, one, few, many)
-  end
-
   def gh_minutes(count)
-    "#{count} #{gh_plural(count, 'minuta', 'minuty', 'minut')}"
+    t('application.helpers.minutes', count: count)
   end
 
   def gh_initials(name)
@@ -64,14 +66,15 @@ def gh_avatar_hue(name)
 
   def gh_when(time)
     case time.to_date
-    when Date.current   then "dziś #{time.strftime('%H:%M')}"
-    when Date.yesterday then "wczoraj #{time.strftime('%H:%M')}"
-    else                     time.strftime('%d.%m, %H:%M')
+    when Date.current   then t('application.helpers.today', time: l(time, format: :gh_time))
+    when Date.yesterday then t('application.helpers.yesterday', time: l(time, format: :gh_time))
+    else                     l(time, format: :gh_day_time)
     end
   end
 
+  # I18n.l rather than l: InviteForm calls this outside a view.
   def gh_stamp(time)
-    time.strftime('%d.%m, %H:%M')
+    I18n.l(time, format: :gh_day_time)
   end
 
   def gh_feed_title(transaction)
@@ -79,11 +82,16 @@ def gh_feed_title(transaction)
 
     case transaction.kind.to_sym
     when :purchase
-      subject ? "Zakup: #{subject.name}" : 'Zakup'
+      if subject
+        t('application.helpers.feed.purchase', name: subject.name)
+      else
+        t('application.helpers.feed.purchase_fallback')
+      end
     when :reward
-      subject&.story_description.presence || subject&.didactic_description.presence || 'Nagroda za aktywność'
+      subject&.story_description.presence || subject&.didactic_description.presence ||
+        t('application.helpers.feed.reward_fallback')
     else
-      'Korekta waluty'
+      t('application.helpers.feed.adjustment')
     end
   end
 
@@ -93,11 +101,22 @@ def gh_percent(value, max)
     ((value.to_f / max) * 100).round.clamp(0, 100)
   end
 
-  def gh_and_list(items)
-    list = Array(items)
-    return list.first.to_s if list.size < 2
+  # Fills a translated template whose slots hold markup rather than text:
+  #   gh_fill(t('items.sentences.max'), holder: ..., percent: tag.b('20%'))
+  # Text around the slots is escaped; html_safe values (tag.b, safe_join) pass
+  # through. item_form_controller.ts fills the same templates on the client.
+  def gh_fill(template, **vars)
+    parts = template.to_s.split(/(%\{\w+\})/).map do |part|
+      key = part[/\A%\{(\w+)\}\z/, 1]
+      key ? vars[key.to_sym] : part
+    end
 
-    "#{list[0..-2].join(', ')} i #{list.last}"
+    safe_join(parts)
+  end
+
+  # "a, b i c" in Polish, "a, b and c" in English (connectors from rails-i18n).
+  def gh_and_list(items)
+    Array(items).map(&:to_s).to_sentence
   end
 
   def gh_glyph(key, css_class: 'gh-card-art-glyph')
diff --git a/app/helpers/badges_helper.rb b/app/helpers/badges_helper.rb
index fdebbe80..1fbaff23 100644
--- a/app/helpers/badges_helper.rb
+++ b/app/helpers/badges_helper.rb
@@ -2,23 +2,23 @@
 
 module BadgesHelper
   def badge_holders_line(count)
-    return 'Nikt jej jeszcze nie ma' if count.zero?
+    return t('badges.helpers.nobody_holds') if count.zero?
 
-    "Ma ją #{count} #{gh_plural(count, 'student', 'studentów', 'studentów')}"
+    t('badges.helpers.holders', count: count)
   end
 
   def badge_discount_label(badge)
     return if badge.discount.to_i.zero?
 
-    "−#{badge.discount}% w sklepie"
+    t('badges.helpers.discount', discount: badge.discount)
   end
 
   def badge_rule(badge)
-    badge.didactic_description.presence || 'Jak zdobyć…'
+    badge.didactic_description.presence || t('badges.helpers.rule_placeholder')
   end
 
   def badge_name(badge)
-    badge.name.presence || 'Nazwa odznaki'
+    badge.name.presence || t('badges.helpers.name_placeholder')
   end
 
   def badge_thumb_subtitle(badge)
diff --git a/app/helpers/currency_transactions_helper.rb b/app/helpers/currency_transactions_helper.rb
index d573c159..14c76df9 100644
--- a/app/helpers/currency_transactions_helper.rb
+++ b/app/helpers/currency_transactions_helper.rb
@@ -11,21 +11,24 @@ module CurrencyTransactionsHelper
   # of its currency and Polish would want a different case here, so the sentence
   # simply does not name it. Same rule as ShopHelper#shop_balance_sentence.
   def ledger_balance_sentence(ledger)
-    safe_join(['Masz ', tag.b(ledger.balance), ' do wydania i ', tag.b(ledger.total), ' zebrane łącznie.'])
+    t('currency_transactions.helpers.balance_sentence_html', balance: tag.b(ledger.balance),
+                                                             total:   tag.b(ledger.total),)
   end
 
   # The teacher's version, which sits on one line beside the filters rather than
   # under a heading.
   def ledger_summary_sentence(ledger)
-    safe_join(['Saldo: ', tag.b(ledger.balance), ', zebrane łącznie: ', tag.b(ledger.total), '.'])
+    t('currency_transactions.helpers.summary_sentence_html', balance: tag.b(ledger.balance),
+                                                             total:   tag.b(ledger.total),)
   end
 
   # The filter chips. Links rather than buttons, because the app's .gh-purchase-filter-chip is
   # keyed on aria-current and because a filter that survives a refresh and can
   # be pasted to someone is worth a query parameter.
   def ledger_filter_chips(ledger, selected, path_for:)
-    safe_join(CurrencyLedger::KINDS.map do |kind, label|
+    safe_join(CurrencyLedger::KINDS.map do |kind|
       current = kind == selected
+      label   = t("currency_transactions.filters.#{kind || 'all'}")
 
       link_to path_for.call(kind), class: 'gh-purchase-filter-chip', 'aria-current': current.to_s do
         safe_join([label, tag.span(ledger.count_for(kind), class: 'gh-count-label')], ' ')
diff --git a/app/helpers/home_helper.rb b/app/helpers/home_helper.rb
index e6889af8..f758f54d 100644
--- a/app/helpers/home_helper.rb
+++ b/app/helpers/home_helper.rb
@@ -3,9 +3,9 @@
 module HomeHelper
   def home_greeting(user)
     first_name = user.full_name.to_s.split.first
-    base_greeting = 'Dzień dobry'
-    return base_greeting if first_name.blank?
 
-    "#{base_greeting}, #{first_name}"
+    return t('home.admin_greeting_anonymous') if first_name.blank?
+
+    t('home.admin_greeting', name: first_name)
   end
 end
diff --git a/app/helpers/items_helper.rb b/app/helpers/items_helper.rb
index a8a0d381..552f5e41 100644
--- a/app/helpers/items_helper.rb
+++ b/app/helpers/items_helper.rb
@@ -2,75 +2,68 @@
 
 module ItemsHelper
   def item_bought_line(count)
-    return 'Jeszcze nikt nie kupił' if count.zero?
+    return t('items.helpers.nobody_bought') if count.zero?
 
-    "Kupiono #{count} #{gh_plural(count, 'raz', 'razy', 'razy')}"
+    t('items.helpers.bought', count: count)
   end
 
   def item_name(item)
-    item.name.presence || 'Nazwa przedmiotu'
+    item.name.presence || t('items.helpers.name_placeholder')
   end
 
   def item_rules(item)
-    item.didactic_description.presence || 'Co daje studentowi…'
+    item.didactic_description.presence || t('items.helpers.rules_placeholder')
   end
 
   def item_unlock_sentence(item)
     rank   = item.unlock_rank&.starting? ? nil : item.unlock_rank
     badges = item.unlock_badges.map(&:name).sort
+    lives  = t(item.can_buy_at_0_lives ? 'items.sentences.lives_yes' : 'items.sentences.lives_no')
 
-    parts = if rank.nil? && badges.empty?
-              ['Każdy student może kupić ten przedmiot']
-            else
-              ['Kupią tylko studenci', *unlock_rank_clause(rank), *unlock_badges_clause(badges)]
-            end
+    return gh_fill(t('items.sentences.unlock_everyone'), lives: lives) if rank.nil? && badges.empty?
 
-    safe_join(parts + [item_lives_clause(item)])
+    gh_fill(t('items.sentences.unlock_restricted'),
+            rank:   unlock_rank_clause(rank),
+            badges: unlock_badges_clause(badges),
+            lives:  lives,)
   end
 
   def item_discount_sentence(item, card, example)
     price = item.price.to_i
-    return safe_join(['Bez zniżek. Każdy kupujący zapłaci ', tag.b(price), '.']) if card.max_discount.zero?
+    return gh_fill(t('items.sentences.no_discount'), price: tag.b(price)) if card.max_discount.zero?
     return if example.none?
 
     paid = PriceCalculatorService.new(price: price, discount: Discount.new(example.percent)).calculate
 
-    saving = tag.b("#{example.percent}%")
-    tail   = [' zaoszczędzi ', saving, ' i zapłaci ', tag.b(paid), " zamiast #{price}."]
-
-    safe_join(['Przykładowo: student', *example_holder_clause(example), *tail])
+    gh_fill(t('items.sentences.example'),
+            holder:  example_holder_clause(example),
+            percent: tag.b("#{example.percent}%"),
+            paid:    tag.b(paid),
+            price:   price,)
   end
 
   def item_discount_max_sentence(card)
     return if card.max_discount.zero?
 
-    saving = tag.b("#{card.max_discount}%")
-
-    safe_join(['Maksymalnie: student', *max_holder_clause(card), ' uzyska zniżkę ', saving, '.'])
+    gh_fill(t('items.sentences.max'), holder: max_holder_clause(card), percent: tag.b("#{card.max_discount}%"))
   end
 
   def item_overlap_warnings(item, card = nil)
     warnings = []
 
-    if card&.capped?
-      warnings << "Zniżki sumują się do #{card.raw_discount}%, a sklep odejmie najwyżej " \
-                  "#{Discount::CAP_VALUE}%. Nadwyżka przepada — rozważ niższe zniżki " \
-                  'przy rangach i odznakach.'
-    end
+    warnings << t('items.sentences.warn_cap', raw: card.raw_discount, cap: Discount::CAP_VALUE) if card&.capped?
 
     if discount_rank_covers_everyone?(item)
       warnings << if item.unlock_rank.starting?
-                    'Zniżka dla rang obejmie każdego kupującego.'
+                    t('items.sentences.warn_rank_everyone')
                   else
-                    "Kupić mogą tylko studenci od rangi #{item.unlock_rank.name}, " \
-                      'więc zniżka dla rang obejmie każdego kupującego.'
+                    t('items.sentences.warn_rank_gate', rank: item.unlock_rank.name)
                   end
     end
 
     overlapping = (item.discount_badges & item.unlock_badges).sort_by { |badge| badge.name.to_s }
     overlapping.each do |badge|
-      warnings << "Odznaka #{badge.name} jest wymagana do zakupu, " \
-                  'więc jej zniżka obejmie każdego kupującego.'
+      warnings << t('items.sentences.warn_badge_required', name: badge.name)
     end
 
     warnings
@@ -79,10 +72,10 @@ def item_overlap_warnings(item, card = nil)
   def item_unlock_rank_options(ranks, selected)
     options = ranks.map do |rank|
       data = { gh_name: rank.name, gh_gates: rank.starting? ? 'false' : 'true' }
-      ["od rangi #{rank.name}", rank.id, { data: data }]
+      [t('items.helpers.unlock_option_rank', name: rank.name), rank.id, { data: data }]
     end
 
-    blank = ['każdy student', '', { data: { gh_name: '', gh_gates: 'false' } }]
+    blank = [t('items.helpers.unlock_option_everyone'), '', { data: { gh_name: '', gh_gates: 'false' } }]
 
     options_for_select([blank] + options, selected)
   end
@@ -92,7 +85,7 @@ def item_discount_rank_options(ranks, selected)
       above = ranks.select { |other| other.required_currency_value.to_i >= rank.required_currency_value.to_i }
       best  = above.max_by { |other| other.discount.to_i }
 
-      label = "od #{rank.name} (−#{rank.discount.to_i}% i więcej)"
+      label = t('items.helpers.discount_option_rank', name: rank.name, discount: rank.discount.to_i)
       data  = {
         gh_discount: best&.discount.to_i,
         gh_name:     best&.name.to_s,
@@ -102,37 +95,42 @@ def item_discount_rank_options(ranks, selected)
       [label, rank.id, { data: data }]
     end
 
-    blank = ['brak', '', { data: { gh_discount: 0, gh_name: '', gh_own: 0, gh_own_name: '' } }]
+    blank_data = { data: { gh_discount: 0, gh_name: '', gh_own: 0, gh_own_name: '' } }
+    blank      = [t('items.helpers.discount_option_none'), '', blank_data]
 
     options_for_select([blank] + options, selected)
   end
 
+  # The templates and plural forms item_form_controller.ts needs to rebuild
+  # the same sentences while the teacher types.
+  def item_form_wording
+    t('items.sentences').merge(
+      t('items.labels').slice(:discount_up_to, :seal_rank, :seal_badge),
+      t('items.helpers').slice(:name_placeholder, :rules_placeholder),
+      buy: t('items.card.buy'),
+    )
+  end
+
   private
 
   def unlock_rank_clause(rank)
-    return [] if rank.nil?
+    return '' if rank.nil?
 
-    [' z rangą ', tag.b(rank.name), ' lub wyższą']
+    gh_fill(t('items.sentences.unlock_rank'), rank: tag.b(rank.name))
   end
 
   def unlock_badges_clause(badges)
-    return [] if badges.empty?
+    return '' if badges.empty?
 
-    noun = badges.size > 1 ? 'wszystkie odznaki' : 'odznakę'
-    [", którzy mają #{noun} ", tag.b(gh_and_list(badges))]
-  end
-
-  def item_lives_clause(item)
-    item.can_buy_at_0_lives ? '. Także przy 0 życiach.' : ', jeśli mają co najmniej 1 życie.'
+    gh_fill(plural_template('items.sentences.unlock_badges', badges.size), badges: tag.b(gh_and_list(badges)))
   end
 
   def example_holder_clause(example)
     names = example.badges.map(&:name)
     return holder_clause(example.rank&.name, nil) if names.empty?
 
-    noun = names.size > 1 ? 'odznakami ' : 'odznaką '
-
-    holder_clause(example.rank&.name, [noun, tag.b(gh_and_list(names))])
+    phrase = gh_fill(plural_template('items.sentences.holder_badges', names.size), badges: tag.b(gh_and_list(names)))
+    holder_clause(example.rank&.name, phrase)
   end
 
   def max_holder_clause(card)
@@ -140,19 +138,27 @@ def max_holder_clause(card)
 
     phrase = case badges.size
              when 0 then nil
-             when 1 then ['odznaką ', tag.b(badges.first.name)]
-             else        ['wszystkimi odznakami']
+             when 1 then gh_fill(plural_template('items.sentences.holder_badges', 1), badges: tag.b(badges.first.name))
+             else        t('items.sentences.holder_all_badges')
              end
 
     holder_clause(card.best_discount_rank&.name, phrase)
   end
 
   def holder_clause(rank_name, badge_phrase)
-    clause = []
-    clause += [' z rangą ', tag.b(rank_name)] if rank_name
-    return clause if badge_phrase.nil?
+    rank = rank_name ? gh_fill(t('items.sentences.holder_rank'), rank: tag.b(rank_name)) : ''
+    return rank if badge_phrase.nil?
+
+    join = rank_name ? 'items.sentences.holder_join_and' : 'items.sentences.holder_join_with'
+    safe_join([rank, gh_fill(t(join), phrase: badge_phrase)])
+  end
+
+  # The raw template of a pluralised key, with its other slots left in place
+  # for gh_fill.
+  def plural_template(key, count)
+    slots = t(key).values.join.scan(/%\{(\w+)\}/).flatten.uniq - ['count']
 
-    clause + [rank_name ? ' oraz ' : ' z ', *badge_phrase]
+    t(key, count: count, **slots.to_h { |slot| [slot.to_sym, "%{#{slot}}"] })
   end
 
   def discount_rank_covers_everyone?(item)
diff --git a/app/helpers/organizations_helper.rb b/app/helpers/organizations_helper.rb
index cd9ff246..c432f6a8 100644
--- a/app/helpers/organizations_helper.rb
+++ b/app/helpers/organizations_helper.rb
@@ -1,23 +1,22 @@
 # frozen_string_literal: true
 
 module OrganizationsHelper
-  USER_ROLE_LABELS = {
-    'student' => 'Student',
-    'teacher' => 'Nauczyciel',
-  }.freeze
-
   def user_role_label(role)
     str_role = role.to_s
-    USER_ROLE_LABELS.fetch(str_role, str_role.humanize)
+    t("organizations.roles.#{str_role}", default: str_role.humanize)
   end
 
   def organization_capacity_lead(organization, members)
-    return "#{members} #{gh_plural(members, 'konto', 'konta', 'kont')} · bez limitu miejsc" if organization.unlimited?
+    if organization.unlimited?
+      return t('organizations.helpers.capacity_unlimited',
+               accounts: t('organizations.helpers.capacity_accounts', count: members),)
+    end
 
     free = [organization.max_members - members, 0].max
-    free_text = gh_plural(free, 'wolne', 'wolne', 'wolnych')
 
-    "#{members} z #{organization.max_members} miejsc zajętych · #{free} #{free_text}"
+    t('organizations.helpers.capacity_limited', members: members,
+                                                max:     organization.max_members,
+                                                free:    t('organizations.helpers.capacity_free', count: free),)
   end
 
   def user_role_options
diff --git a/app/helpers/ranks_helper.rb b/app/helpers/ranks_helper.rb
index cfccd455..57478bb4 100644
--- a/app/helpers/ranks_helper.rb
+++ b/app/helpers/ranks_helper.rb
@@ -2,33 +2,37 @@
 
 module RanksHelper
   def rank_summary(rank)
-    opening = rank.starting? ? 'Ranga startowa' : "Od #{rank.required_currency_value} zebranych"
+    opening = rank.starting? ? t('ranks.helpers.starting') : t('ranks.helpers.from', min: rank.required_currency_value)
 
-    return "#{opening}, bez zniżki" if rank.discount.to_i.zero?
+    return t('ranks.helpers.summary_no_discount', opening: opening) if rank.discount.to_i.zero?
 
-    "#{opening}, −#{rank.discount}% w sklepie"
+    t('ranks.helpers.summary_discount', opening: opening, discount: rank.discount)
   end
 
   def rank_summary_sentences(rank)
-    opening = rank.starting? ? 'Ranga startowa.' : "Od #{rank.required_currency_value} zebranych."
+    opening = if rank.starting?
+                t('ranks.helpers.starting_sentence')
+              else
+                t('ranks.helpers.from_sentence', min: rank.required_currency_value)
+              end
 
     return opening if rank.discount.to_i.zero?
 
-    "#{opening} Daje −#{rank.discount}% w sklepie."
+    "#{opening} #{t('ranks.helpers.gives_discount', discount: rank.discount)}"
   end
 
   def rank_ladder_terms(rank)
-    return "−#{rank.discount}% w sklepie" if rank.discount.to_i.positive?
-    return 'Ranga startowa' if rank.starting?
+    return t('ranks.helpers.discount', discount: rank.discount) if rank.discount.to_i.positive?
+    return t('ranks.helpers.starting') if rank.starting?
 
-    'Bez zniżki'
+    t('ranks.helpers.no_discount')
   end
 
   def rank_reward_line(rank)
-    line = "Wymagane: #{rank.required_currency_value.to_i} zebranych."
+    line = t('ranks.helpers.required', min: rank.required_currency_value.to_i)
 
     return line if rank.discount.to_i.zero?
 
-    "#{line} Daje −#{rank.discount}% w sklepie."
+    "#{line} #{t('ranks.helpers.gives_discount', discount: rank.discount)}"
   end
 end
diff --git a/app/helpers/shop_helper.rb b/app/helpers/shop_helper.rb
index 6ea81d66..327637db 100644
--- a/app/helpers/shop_helper.rb
+++ b/app/helpers/shop_helper.rb
@@ -7,7 +7,7 @@ module ShopHelper
   # declined: a group holds one nominative form ("marchewki") and Polish wants
   # the genitive here. ranks/_teacher_ladder.html.haml:8 makes the same dodge.
   def shop_balance_sentence(balance)
-    safe_join(['Masz ', tag.b(balance), ' do wydania.'])
+    t('shop.helpers.balance_html', balance: tag.b(balance))
   end
 
   # "Twoje odznaki Mechanik i Nawigator obniżają ceny niektórych przedmiotów."
@@ -17,17 +17,18 @@ def shop_discount_sentence(badges)
     return if badges.empty?
 
     names = badges.map { |badge| tag.b(badge.name) }
-    lead  = gh_plural(badges.size, 'Twoja odznaka ', 'Twoje odznaki ', 'Twoje odznaki ')
-    verb  = gh_plural(badges.size, ' obniża ', ' obniżają ', ' obniżają ')
 
-    safe_join([lead, gh_and_list_html(names), verb, 'ceny niektórych przedmiotów.'])
+    t('shop.helpers.discount_badges_html', count: badges.size, badges: gh_and_list_html(names))
   end
 
   # gh_and_list, but for parts that are already markup: Array#join would hand
-  # safe_join a plain String and every <b> would come back escaped.
+  # safe_join a plain String and every <b> would come back escaped. The
+  # connectors are rails-i18n's, the same ones Array#to_sentence uses.
   def gh_and_list_html(parts)
     return parts.first if parts.size < 2
+    return safe_join(parts, t('support.array.two_words_connector')) if parts.size == 2
 
-    safe_join([safe_join(parts[0..-2], ', '), parts.last], ' i ')
+    safe_join([safe_join(parts[0..-2], t('support.array.words_connector')), parts.last],
+              t('support.array.last_word_connector'),)
   end
 end
diff --git a/app/helpers/story_group_invites_helper.rb b/app/helpers/story_group_invites_helper.rb
index 2da94dac..e10c129b 100644
--- a/app/helpers/story_group_invites_helper.rb
+++ b/app/helpers/story_group_invites_helper.rb
@@ -21,35 +21,49 @@ def invite_qr_code(invite)
   end
 
   def invite_uses_label(invite)
-    return "#{invite.uses}, bez limitu" if invite.max_uses.nil?
+    return t('story_group_invites.helpers.uses_unlimited', uses: invite.uses) if invite.max_uses.nil?
 
-    "#{invite.uses} z #{invite.max_uses}"
+    t('story_group_invites.helpers.uses_limited', uses: invite.uses, max: invite.max_uses)
   end
 
   def invite_expiry_label(invite)
-    return 'Bez daty ważności' if invite.expires_at.nil?
+    return t('story_group_invites.helpers.no_expiry') if invite.expires_at.nil?
 
-    "#{invite.expire_time_condition ? 'Wygasa' : 'Wygasło'} #{gh_stamp(invite.expires_at)}"
+    key = invite.expire_time_condition ? 'expires' : 'expired'
+    t("story_group_invites.helpers.#{key}", date: gh_stamp(invite.expires_at))
   end
 
   def invite_stat_sentence(invite)
     expiry = if invite.expires_at.nil?
-               'Bez daty ważności.'
+               t('story_group_invites.helpers.no_expiry')
              else
-               "Wygasa #{gh_stamp(invite.expires_at)}."
+               t('story_group_invites.helpers.expires', date: gh_stamp(invite.expires_at))
              end
 
-    "Użycia: #{invite_uses_label(invite)}. #{expiry}"
+    t('story_group_invites.helpers.stat_sentence', uses: invite_uses_label(invite), expiry: expiry)
   end
 
   def invite_code_aria_label(invite)
-    "Kod: #{invite.code.chars.join(' ')}"
+    t('story_group_invites.helpers.code_label', code: invite.code.chars.join(' '))
   end
 
   def invite_option_label(invite)
-    uses     = invite.max_uses.nil? ? 'bez limitu' : "#{invite.uses} z #{invite.max_uses}"
-    validity = invite.expires_at.nil? ? 'bezterminowo' : "ważne do #{gh_stamp(invite.expires_at)}"
+    uses = if invite.max_uses.nil?
+             t('story_group_invites.helpers.option_unlimited')
+           else
+             t('story_group_invites.helpers.uses_limited', uses: invite.uses, max: invite.max_uses)
+           end
+    validity = if invite.expires_at.nil?
+                 t('story_group_invites.helpers.option_no_expiry')
+               else
+                 t('story_group_invites.helpers.option_valid_until', date: gh_stamp(invite.expires_at))
+               end
 
-    "#{invite.code} – #{uses}, #{validity}"
+    t('story_group_invites.helpers.option', code: invite.code, uses: uses, validity: validity)
+  end
+
+  # What invite_form_controller.ts needs to rebuild the form's summary line.
+  def invite_form_wording
+    t('story_group_invites.summary').merge(month_names: t('date.abbr_month_names'))
   end
 end
diff --git a/app/helpers/story_groups_helper.rb b/app/helpers/story_groups_helper.rb
index be0251ef..41b00a1c 100644
--- a/app/helpers/story_groups_helper.rb
+++ b/app/helpers/story_groups_helper.rb
@@ -6,31 +6,29 @@ module StoryGroupsHelper
   def overview_teacher_lead(story_group, students_count)
     return story_group.description if story_group.description.present?
 
-    "#{students_count} #{gh_plural(students_count, 'student', 'studenci', 'studentów')} w tej grupie. " \
-      'Dodaj opis w ustawieniach, żeby powitać nowe osoby.'
+    t('story_groups.helpers.teacher_lead', count: students_count)
   end
 
   def overview_next_rank_line(missing, next_rank)
-    line = "Jeszcze #{missing} do rangi #{next_rank.name}."
+    line = t('story_groups.helpers.next_rank', missing: missing, rank: next_rank.name)
     return line unless next_rank.discount.to_i.positive?
 
-    "#{line} Ta ranga daje −#{next_rank.discount}% w sklepie."
+    "#{line} #{t('story_groups.helpers.next_rank_discount', discount: next_rank.discount)}"
   end
 
   def ranking_visibility_note(story_group)
-    return 'Ranking jest wyłączony — studenci nie widzą tego podium.' unless story_group.ranking_enabled?
-    return 'Studenci widzą pełny ranking, pod pseudonimami.' if story_group.ranking_full?
+    return t('story_groups.helpers.ranking_off') unless story_group.ranking_enabled?
+    return t('story_groups.helpers.ranking_full') if story_group.ranking_full?
 
-    'Studenci widzą podium i własne miejsce, pod pseudonimami.'
+    t('story_groups.helpers.ranking_podium')
   end
 
   def overview_place_line(place)
-    "#{place}. miejsce w rankingu grupy"
+    t('story_groups.helpers.place', place: place)
   end
 
   def overview_hand_line(affordable)
-    "Dobierz coś w sklepie. Stać cię teraz na #{affordable} " \
-      "#{gh_plural(affordable, 'przedmiot', 'przedmioty', 'przedmiotów')}."
+    t('story_groups.helpers.hand', count: affordable)
   end
 
   def overview_hand_rotation(index, count)
diff --git a/app/helpers/students_badges_helper.rb b/app/helpers/students_badges_helper.rb
index 46ebfb7c..d862cd06 100644
--- a/app/helpers/students_badges_helper.rb
+++ b/app/helpers/students_badges_helper.rb
@@ -4,13 +4,13 @@
 module StudentsBadgesHelper
   # "Sebastian ma 2 z 8 odznak." — the assign dialog's sub-line.
   def badge_assign_lead(student, held, total)
-    "#{student.display_name} ma #{held} z #{total} #{gh_plural(total, 'odznaki', 'odznak', 'odznak')}."
+    t('students_badges.helpers.assign_lead', name: student.display_name, held: held, count: total)
   end
 
   # The right-hand label on a row of the picker: what the badge is worth, or
   # that this student already has it.
   def badge_pick_status(badge, held)
-    return 'Ma już' if held
+    return t('students_badges.helpers.owned') if held
     return '−0%' if badge.discount.to_i.zero?
 
     "−#{badge.discount.to_i}%"
@@ -19,34 +19,35 @@ def badge_pick_status(badge, held)
   # What awarding this badge will actually do. Rendered once per badge, hidden,
   # so badge_picker_controller reveals one rather than building a sentence.
   def badge_effect_sentence(badge)
-    parts = [
-      'Po przyznaniu: ',
-      tag.b("−#{badge.discount.to_i}%"),
-      ' na przedmioty, które uwzględniają tę odznakę',
-    ]
-
     unlocking   = badge.unlocking_items.order(:name).pluck(:name)
     discounting = badge.dependent_items.order(:name).pluck(:name) - unlocking
-    parts << " (#{gh_and_list(discounting)})" if discounting.any?
-    parts << '.'
 
-    parts += [' Odblokuje zakup: ', tag.b(gh_and_list(unlocking)), '.'] if unlocking.any?
+    t('students_badges.helpers.effect_html',
+      discount:    tag.b("−#{badge.discount.to_i}%"),
+      discounting: badge_effect_discounting(discounting),
+      unlocks:     badge_effect_unlocks(unlocking),)
+  end
 
-    parts << ' Zobaczy ją w swojej talii.'
+  def badge_effect_discounting(names)
+    return '' if names.empty?
 
-    safe_join(parts)
+    t('students_badges.helpers.effect_discounting', items: gh_and_list(names))
+  end
+
+  def badge_effect_unlocks(names)
+    return '' if names.empty?
+
+    t('students_badges.helpers.effect_unlocks_html', items: tag.b(gh_and_list(names)))
   end
 
   # What revoking it costs. The purchase clause only when the badge is a key to
   # something; items already bought are never taken back.
   def badge_revoke_sentence(student, badge)
-    parts = [student.display_name, ' straci zniżkę ', tag.b("−#{badge.discount.to_i}%")]
-
     unlocking = badge.unlocking_items.order(:name).pluck(:name)
-    parts << " i możliwość zakupu: #{gh_and_list(unlocking)}" if unlocking.any?
-
-    parts << '. Kupione wcześniej przedmioty zostają.'
 
-    safe_join(parts)
+    t('students_badges.helpers.revoke_html',
+      name:      student.display_name,
+      discount:  tag.b("−#{badge.discount.to_i}%"),
+      unlocking: unlocking.any? ? t('students_badges.helpers.revoke_unlocking', items: gh_and_list(unlocking)) : '',)
   end
 end
diff --git a/app/helpers/students_helper.rb b/app/helpers/students_helper.rb
index e545b0db..480b4338 100644
--- a/app/helpers/students_helper.rb
+++ b/app/helpers/students_helper.rb
@@ -3,19 +3,18 @@
 # Screen-specific labels live in the screen's own helper, not in ApplicationHelper.
 module StudentsHelper
   def student_list_lead(list)
-    lead = ['Życie odbierasz za nieusprawiedliwioną nieobecność.']
+    lead = [t('students.helpers.list_lead')]
     return safe_join(lead) if list.zero_lives.zero?
 
-    zero = list.zero_lives
-
     safe_join(lead + [' ',
-                      tag.b("#{zero} #{gh_plural(zero, 'student ma', 'studentów ma', 'studentów ma')} 0 żyć"),
-                      ' i kupi tylko przedmioty dostępne przy 0 życiach.',])
+                      tag.b(t('students.helpers.zero_lives', count: list.zero_lives)),
+                      ' ',
+                      t('students.helpers.zero_lives_tail'),])
   end
 
   def student_list_subtitle(student)
     parts = []
-    parts << "„#{student.nickname}”" if student.nickname.present?
+    parts << t('students.helpers.nickname_quoted', nickname: student.nickname) if student.nickname.present?
     parts << student.email
 
     parts.join(' · ')
@@ -27,9 +26,11 @@ def student_list_subtitle(student)
   # student who joined without an index number simply does not get that half.
   def student_sheet_subtitle(student)
     parts = []
-    parts << "Pseudonim: #{student.nickname}" if student.nickname.present?
+    parts << t('students.helpers.nickname', nickname: student.nickname) if student.nickname.present?
     parts << student.email
-    parts << "indeks #{student.university_number}" if student.university_number.present?
+    if student.university_number.present?
+      parts << t('students.helpers.university_number', number: student.university_number)
+    end
 
     parts.join(', ')
   end
@@ -39,7 +40,9 @@ def student_sheet_subtitle(student)
   def student_rank_progress_line(sheet)
     return if sheet.next_rank.nil?
 
-    "#{sheet.total} z #{sheet.next_rank.required_currency_value} do rangi #{sheet.next_rank.name}"
+    t('students.helpers.rank_progress', total:    sheet.total,
+                                        required: sheet.next_rank.required_currency_value,
+                                        rank:     sheet.next_rank.name,)
   end
 
   # What "Usuń z grupy" costs, spelled out in numbers. Nothing is soft-deleted
@@ -48,18 +51,11 @@ def student_rank_progress_line(sheet)
   def student_removal_losses(sheet)
     losses = []
 
-    if sheet.badges.any?
-      count = sheet.badges.size
-      losses << "#{count} #{gh_plural(count, 'odznakę', 'odznaki', 'odznak')}"
-    end
-
-    if sheet.purchases.any?
-      count = sheet.purchases.size
-      losses << "#{count} #{gh_plural(count, 'przedmiot', 'przedmioty', 'przedmiotów')}"
-    end
+    losses << t('students.helpers.losses.badges', count: sheet.badges.size) if sheet.badges.any?
+    losses << t('students.helpers.losses.items', count: sheet.purchases.size) if sheet.purchases.any?
 
     entries = sheet.ledger.size
-    losses << "całą historię waluty (#{entries} #{gh_plural(entries, 'wpis', 'wpisy', 'wpisów')})" if entries.positive?
+    losses << t('students.helpers.losses.ledger', count: entries) if entries.positive?
 
     losses
   end
diff --git a/app/helpers/students_items_helper.rb b/app/helpers/students_items_helper.rb
index d3418fba..4622788f 100644
--- a/app/helpers/students_items_helper.rb
+++ b/app/helpers/students_items_helper.rb
@@ -4,30 +4,29 @@
 module StudentsItemsHelper
   # "3 przedmioty. Wykorzystanie przedmiotu zgłaszasz prowadzącemu na zajęciach."
   def inventory_lead(count)
-    "#{count} #{gh_plural(count, 'przedmiot', 'przedmioty', 'przedmiotów')}. " \
-      'Wykorzystanie przedmiotu zgłaszasz prowadzącemu na zajęciach.'
+    t('students_items.helpers.inventory_lead', count: count)
   end
 
   # The student's own card foot: "Kupione 12.06, 10:21, za 15".
   def purchase_line(purchase)
-    "Kupione #{gh_when(purchase.created_at)}, za #{purchase.price_paid}"
+    t('students_items.helpers.purchase_line', when: gh_when(purchase.created_at), price: purchase.price_paid)
   end
 
   # The teacher's, on the sheet's Przedmioty tab. The price paid is in the cost
   # chip there, so this names the discount instead — what the item costs anyone
   # else is the part the teacher cannot see from the number alone.
   def purchase_teacher_line(purchase)
-    line = "Kupione #{gh_when(purchase.created_at)}"
-    list = purchase.item&.price.to_i
+    bought_at = gh_when(purchase.created_at)
+    list      = purchase.item&.price.to_i
 
-    return line if purchase.price_paid.to_i >= list
+    return t('students_items.helpers.purchase_teacher_line', when: bought_at) if purchase.price_paid.to_i >= list
 
-    "#{line}, ze zniżką z #{list}"
+    t('students_items.helpers.purchase_teacher_discount', when: bought_at, list: list)
   end
 
   # "Stać cię teraz na 3 przedmioty w sklepie." — the dashed slot that closes
   # the grid, which is the whole reason this screen links to the shop at all.
   def inventory_shop_line(count)
-    "Stać cię teraz na #{count} #{gh_plural(count, 'przedmiot', 'przedmioty', 'przedmiotów')} w sklepie."
+    t('students_items.helpers.shop_line', count: count)
   end
 end
diff --git a/app/helpers/teachers_helper.rb b/app/helpers/teachers_helper.rb
index 163cb4e4..2a9e224b 100644
--- a/app/helpers/teachers_helper.rb
+++ b/app/helpers/teachers_helper.rb
@@ -2,29 +2,22 @@
 
 module TeachersHelper
   def teacher_list_lead(manage:)
-    opening = 'Nauczyciele wspomagający pomagają prowadzić tę grupę.'
+    tail = manage ? t('teachers.helpers.lead_manage') : t('teachers.helpers.lead_read_only')
 
-    return "#{opening} Grupę może usunąć tylko właściciel." if manage
-
-    "#{opening} Dodawać i usuwać nauczycieli może tylko właściciel grupy."
+    "#{t('teachers.helpers.lead')} #{tail}"
   end
 
   def teacher_added_on(time)
-    time.to_date.strftime('%d.%m.%Y')
+    l(time.to_date, format: :default)
   end
 
   def teacher_pool_hint(size)
-    count = gh_plural(size,
-                      "jest #{size} nauczyciel",
-                      "są #{size} nauczyciele",
-                      "jest #{size} nauczycieli",)
-
-    "Wpisz co najmniej 2 znaki imienia, nazwiska albo e-maila. W Twojej uczelni #{count}."
+    t('teachers.helpers.pool_hint', count: size)
   end
 
   def teacher_candidate_subtitle(candidate, cross_university:)
     return candidate.email unless cross_university && candidate.person.university_name.present?
 
-    "#{candidate.email}, #{candidate.person.university_name}"
+    t('teachers.helpers.candidate', email: candidate.email, university: candidate.person.university_name)
   end
 end
diff --git a/app/javascript/controllers/badge_form_controller.ts b/app/javascript/controllers/badge_form_controller.ts
index d9f49fed..b2e1bfc3 100644
--- a/app/javascript/controllers/badge_form_controller.ts
+++ b/app/javascript/controllers/badge_form_controller.ts
@@ -10,6 +10,16 @@ class BadgeFormController extends Controller<HTMLFormElement> {
     "flip", "side",
   ]
 
+  static values = {
+    namePlaceholder: String,
+    rulePlaceholder: String,
+    discountLabel: String,
+  }
+
+  declare readonly namePlaceholderValue: string
+  declare readonly rulePlaceholderValue: string
+  declare readonly discountLabelValue: string
+
   declare readonly nameTarget: HTMLInputElement
   declare readonly ruleTarget: HTMLTextAreaElement
   declare readonly storyTarget: HTMLTextAreaElement
@@ -37,18 +47,18 @@ class BadgeFormController extends Controller<HTMLFormElement> {
     const story = this.storyTarget.value.trim()
     const discount = Math.max(0, parseInt(this.discountTarget.value, 10) || 0)
 
-    this.placeholder(this.frontNameTarget, name, "Nazwa odznaki")
-    this.placeholder(this.backNameTarget, name, "Nazwa odznaki")
-    this.placeholder(this.frontRulesTarget, rule, "Jak zdobyć…")
-    this.backHowTarget.textContent = rule || "Jak zdobyć…"
+    this.placeholder(this.frontNameTarget, name, this.namePlaceholderValue)
+    this.placeholder(this.backNameTarget, name, this.namePlaceholderValue)
+    this.placeholder(this.frontRulesTarget, rule, this.rulePlaceholderValue)
+    this.backHowTarget.textContent = rule || this.rulePlaceholderValue
 
     this.frontFlavorTarget.textContent = story
     this.frontFlavorTarget.hidden = story === ""
 
-    this.frontTagTarget.textContent = `−${discount}% w sklepie`
+    this.frontTagTarget.textContent = this.discountLabelValue.replace("%{discount}", String(discount))
     this.frontTagTarget.hidden = discount === 0
 
-    this.thumbNameTarget.textContent = name || "Nazwa odznaki"
+    this.thumbNameTarget.textContent = name || this.namePlaceholderValue
     this.thumbSubTarget.textContent = story || rule
 
     this.renderArt()
diff --git a/app/javascript/controllers/grading_controller.ts b/app/javascript/controllers/grading_controller.ts
index 6575c055..7b919cbf 100644
--- a/app/javascript/controllers/grading_controller.ts
+++ b/app/javascript/controllers/grading_controller.ts
@@ -1,6 +1,16 @@
 import { application } from "@controllers/application"
 import { Controller, type ActionEvent } from "@hotwired/stimulus"
 import { TOAST_EVENT, type ToastDetail } from "@controllers/toast_controller"
+import { interpolate, pluralize, type PluralForms } from "@utils/i18n"
+
+interface Wording {
+  cells: PluralForms
+  students: PluralForms
+  recipients: PluralForms
+  cell_empty: string
+  cell_marked: string
+  locked: string
+}
 
 class GradingController extends Controller<HTMLElement> {
   static targets = [
@@ -11,11 +21,7 @@ class GradingController extends Controller<HTMLElement> {
   ]
 
   static values = {
-    cells: Array,
-    students: Array,
-    recipients: Array,
-    states: Array,
-    currency: String,
+    i18n: Object,
   }
 
   declare readonly searchTarget: HTMLInputElement
@@ -34,11 +40,7 @@ class GradingController extends Controller<HTMLElement> {
   declare readonly reviewRowTargets: HTMLElement[]
   declare readonly reviewChipTargets: HTMLElement[]
   declare readonly reviewConfirmSumTarget: HTMLElement
-  declare readonly cellsValue: string[]
-  declare readonly studentsValue: string[]
-  declare readonly recipientsValue: string[]
-  declare readonly statesValue: string[]
-  declare readonly currencyValue: string
+  declare readonly i18nValue: Wording
 
   connect() {
     this.clearTarget.hidden = false
@@ -90,7 +92,7 @@ class GradingController extends Controller<HTMLElement> {
 
   locked() {
     const detail: ToastDetail = {
-      message: "To pole jest już przyznane i nie można go cofnąć.",
+      message: this.i18nValue.locked,
       icon: "fa-lock",
     }
 
@@ -150,10 +152,8 @@ class GradingController extends Controller<HTMLElement> {
     const students = new Set(marked.map((cell) => this.studentOf(cell))).size
     const sum = marked.reduce((total, cell) => total + rewardOf(cell), 0)
 
-    this.barCellsTarget.textContent =
-      `Zaznaczone teraz: ${count} ${plural(count, this.cellsValue)}`
-    this.barStudentsTarget.textContent =
-      `u ${students} ${plural(students, this.studentsValue)}, razem`
+    this.barCellsTarget.textContent = pluralize(this.i18nValue.cells, count)
+    this.barStudentsTarget.textContent = pluralize(this.i18nValue.students, students)
     this.barSumTarget.textContent = `+${sum}`
   }
 
@@ -185,14 +185,14 @@ class GradingController extends Controller<HTMLElement> {
     const students = byStudent.size
 
     this.reviewSumTarget.textContent = String(sum)
-    this.reviewStudentsTarget.textContent = `${students} ${plural(students, this.recipientsValue)}`
+    this.reviewStudentsTarget.textContent = pluralize(this.i18nValue.recipients, students)
     this.reviewConfirmSumTarget.textContent = String(sum)
   }
 
   private relabel(box: HTMLInputElement) {
-    const [empty, marked] = this.statesValue
+    const template = box.checked ? this.i18nValue.cell_marked : this.i18nValue.cell_empty
 
-    box.setAttribute("aria-label", `${box.dataset.ghLabel ?? ""}: ${box.checked ? marked : empty}`)
+    box.setAttribute("aria-label", interpolate(template, { label: box.dataset.ghLabel ?? "" }))
   }
 
   private get visibleCells(): HTMLElement[] {
@@ -234,15 +234,4 @@ function fold(text: string): string {
     .replace(/ł/g, "l")
 }
 
-function plural(count: number, forms: string[]): string {
-  const [one, few, many] = forms
-  const last = count % 10
-  const teens = count % 100
-
-  if (count === 1) return one
-  if (last >= 2 && last <= 4 && (teens < 12 || teens > 14)) return few
-
-  return many
-}
-
 application.register("grading", GradingController)
diff --git a/app/javascript/controllers/group_wizard_controller.ts b/app/javascript/controllers/group_wizard_controller.ts
index 15adad7b..2b28dfb0 100644
--- a/app/javascript/controllers/group_wizard_controller.ts
+++ b/app/javascript/controllers/group_wizard_controller.ts
@@ -1,5 +1,20 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { interpolate } from "@utils/i18n"
+
+interface Wording {
+  review_step: string
+  summary_step: string
+  counter: string
+  next: string
+  create_short: string
+  create_quick: string
+  create_empty: string
+  name_placeholder: string
+  currency_placeholder: string
+  ranking_off: string
+  ranking_on: string
+}
 
 const LAST_STEP = 3
 
@@ -22,7 +37,7 @@ class GroupWizardController extends Controller<HTMLElement> {
     "back", "cancel", "next", "nextLabel", "nextLabelShort", "nextIcon", "submit", "counter",
   ]
 
-  static values = { presetUrl: String }
+  static values = { presetUrl: String, i18n: Object }
 
   declare readonly formTarget: HTMLFormElement
   declare readonly gridTarget: HTMLElement
@@ -68,6 +83,7 @@ class GroupWizardController extends Controller<HTMLElement> {
   declare readonly submitTarget: HTMLInputElement
   declare readonly counterTarget: HTMLElement
   declare readonly presetUrlValue: string
+  declare readonly i18nValue: Wording
 
   private step = 0
 
@@ -180,7 +196,7 @@ class GroupWizardController extends Controller<HTMLElement> {
       this.stepTickTargets[index].hidden = !done
     })
 
-    this.stepLabelTargets[LAST_STEP].textContent = this.quick ? "Przegląd zestawu" : "Podsumowanie"
+    this.stepLabelTargets[LAST_STEP].textContent = this.quick ? this.i18nValue.review_step : this.i18nValue.summary_step
   }
 
   private renderPanels() {
@@ -197,23 +213,23 @@ class GroupWizardController extends Controller<HTMLElement> {
   }
 
   private renderBar() {
-    this.counterTarget.textContent = `Krok ${this.step + 1} z ${LAST_STEP + 1}`
+    this.counterTarget.textContent = interpolate(this.i18nValue.counter, { step: this.step + 1, total: LAST_STEP + 1 })
     this.backTarget.hidden = this.step === 0
     this.cancelTarget.hidden = this.step !== 0
 
     const last = this.step === LAST_STEP
 
     this.nextIconTarget.hidden = last
-    this.nextLabelTarget.textContent = last ? this.createLabel : "Dalej"
-    this.nextLabelShortTarget.textContent = last ? "Utwórz grupę" : "Dalej"
+    this.nextLabelTarget.textContent = last ? this.createLabel : this.i18nValue.next
+    this.nextLabelShortTarget.textContent = last ? this.i18nValue.create_short : this.i18nValue.next
   }
 
   private get createLabel(): string {
-    return this.quick ? "Utwórz grupę z zestawem" : "Utwórz pustą grupę"
+    return this.quick ? this.i18nValue.create_quick : this.i18nValue.create_empty
   }
 
   private renderArt() {
-    this.nameEchoTarget.textContent = this.nameTarget.value.trim() || "Nazwa grupy"
+    this.nameEchoTarget.textContent = this.nameTarget.value.trim() || this.i18nValue.name_placeholder
     this.nameEchoTarget.classList.toggle("gh-placeholder-text", this.nameTarget.value.trim() === "")
 
     const art = this.chosen("[icon_glyph]")
@@ -242,7 +258,7 @@ class GroupWizardController extends Controller<HTMLElement> {
     const name = this.currencyTarget.value.trim()
 
     this.currencyEchoTargets.forEach((echo) => {
-      echo.textContent = name || "Marchewek"
+      echo.textContent = name || this.i18nValue.currency_placeholder
       echo.classList.toggle("gh-placeholder-text", name === "")
     })
 
@@ -309,13 +325,13 @@ class GroupWizardController extends Controller<HTMLElement> {
     this.sumLivesTarget.textContent = this.livesField?.value ?? ""
     this.sumRankingTarget.textContent = this.rankingTarget.checked ?
       this.rankingLabel :
-      "Wyłączony"
+      this.i18nValue.ranking_off
   }
 
   private get rankingLabel(): string {
     const select = this.rankingModeTarget.querySelector<HTMLSelectElement>("select")
 
-    return select?.selectedOptions[0]?.textContent?.trim() ?? "Widoczny dla studentów"
+    return select?.selectedOptions[0]?.textContent?.trim() ?? this.i18nValue.ranking_on
   }
 
   private get livesField(): HTMLInputElement | null {
diff --git a/app/javascript/controllers/image_crop_controller.ts b/app/javascript/controllers/image_crop_controller.ts
index ff886bc5..2d57742b 100644
--- a/app/javascript/controllers/image_crop_controller.ts
+++ b/app/javascript/controllers/image_crop_controller.ts
@@ -14,6 +14,7 @@ class ImageCropController extends Controller<HTMLElement> {
   static values = {
     aspect: { type: Number, default: 1.6 },
     width: { type: Number, default: 1024 },
+    alt: String,
   }
 
   declare readonly inputTarget: HTMLInputElement
@@ -25,6 +26,7 @@ class ImageCropController extends Controller<HTMLElement> {
   declare readonly hasOwnPreviewTarget: boolean
   declare readonly aspectValue: number
   declare readonly widthValue: number
+  declare readonly altValue: string
 
   private cropper: Cropper | null = null
   private objectUrl: string | null = null
@@ -64,7 +66,7 @@ class ImageCropController extends Controller<HTMLElement> {
 
     const image = document.createElement("img")
     image.src = this.objectUrl
-    image.alt = "Wgrana grafika"
+    image.alt = this.altValue
     this.boxTarget.replaceChildren(image)
 
     this.cropper = new Cropper(image, { template: this.template })
diff --git a/app/javascript/controllers/invite_form_controller.ts b/app/javascript/controllers/invite_form_controller.ts
index 87a61106..10c490c9 100644
--- a/app/javascript/controllers/invite_form_controller.ts
+++ b/app/javascript/controllers/invite_form_controller.ts
@@ -1,18 +1,24 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { interpolate, pluralize, pluralTemplate, type PluralForms } from "@utils/i18n"
+
+// StoryGroupInvitesHelper#invite_form_wording — story_group_invites.summary.*
+// plus the locale's short month names, so the date reads like gh_stamp's.
+interface Wording {
+  sentence: string
+  limit: PluralForms
+  no_limit: string
+  expiry: string
+  no_expiry: string
+  unit: PluralForms
+  stamp: string
+  month_names: (string | null)[]
+}
 
 class InviteFormController extends Controller {
   static targets = ["limitSwitch", "expirySwitch", "maxUses", "unit", "date", "time", "summary"]
 
-  static values = {
-    summaryPrefix: String,
-    limitPrefix: String,
-    noLimit: String,
-    expiryPrefix: String,
-    noExpiry: String,
-    peopleForms: Array,
-    unitForms: Array,
-  }
+  static values = { i18n: Object }
 
   declare readonly limitSwitchTarget: HTMLInputElement
   declare readonly expirySwitchTarget: HTMLInputElement
@@ -22,20 +28,14 @@ class InviteFormController extends Controller {
   declare readonly timeTarget: HTMLInputElement
   declare readonly summaryTarget: HTMLElement
 
-  declare readonly summaryPrefixValue: string
-  declare readonly limitPrefixValue: string
-  declare readonly noLimitValue: string
-  declare readonly expiryPrefixValue: string
-  declare readonly noExpiryValue: string
-  declare readonly peopleFormsValue: string[]
-  declare readonly unitFormsValue: string[]
+  declare readonly i18nValue: Wording
 
   connect() {
     this.refresh()
   }
 
   refresh() {
-    this.unitTarget.textContent = this.plural(this.unitFormsValue, this.maxUses)
+    this.unitTarget.textContent = pluralTemplate(this.i18nValue.unit, this.maxUses)
     this.summaryTarget.textContent = this.summary()
   }
 
@@ -55,21 +55,19 @@ class InviteFormController extends Controller {
   }
 
   private summary(): string {
-    return `${this.summaryPrefixValue} ${this.limitPhrase()} ${this.expiryPhrase()}.`
+    return interpolate(this.i18nValue.sentence, { limit: this.limitPhrase(), expiry: this.expiryPhrase() })
   }
 
   private limitPhrase(): string {
-    if (!this.limitSwitchTarget.checked) return this.noLimitValue
+    if (!this.limitSwitchTarget.checked) return this.i18nValue.no_limit
 
-    const count = this.maxUses
-
-    return `${this.limitPrefixValue} ${count} ${this.plural(this.peopleFormsValue, count)}`
+    return pluralize(this.i18nValue.limit, this.maxUses)
   }
 
   private expiryPhrase(): string {
-    if (!this.expirySwitchTarget.checked) return this.noExpiryValue
+    if (!this.expirySwitchTarget.checked) return this.i18nValue.no_expiry
 
-    return `${this.expiryPrefixValue} ${this.stamp()}`
+    return interpolate(this.i18nValue.expiry, { date: this.stamp() })
   }
 
   private stamp(): string {
@@ -77,24 +75,18 @@ class InviteFormController extends Controller {
 
     if (!year || !month || !day) return ""
 
-    return `${day}.${month}, ${this.timeTarget.value}`
+    return interpolate(this.i18nValue.stamp, {
+      day,
+      month,
+      dayNumber: Number(day),
+      monthName: this.i18nValue.month_names[Number(month)] ?? month,
+      time: this.timeTarget.value,
+    })
   }
 
   private get maxUses(): number {
     return Number.parseInt(this.maxUsesTarget.value, 10) || 0
   }
-
-  private plural(forms: string[], count: number): string {
-    const [one, few, many] = forms
-    const n = Math.abs(count)
-    const lastTwo = n % 100
-    const lastOne = n % 10
-
-    if (n === 1) return one
-    if (lastOne >= 2 && lastOne <= 4 && (lastTwo < 12 || lastTwo > 14)) return few
-
-    return many
-  }
 }
 
 application.register("invite-form", InviteFormController)
diff --git a/app/javascript/controllers/item_form_controller.ts b/app/javascript/controllers/item_form_controller.ts
index 5bd52c1d..7678fb41 100644
--- a/app/javascript/controllers/item_form_controller.ts
+++ b/app/javascript/controllers/item_form_controller.ts
@@ -1,5 +1,6 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { andList, interpolate, locale, pluralTemplate, type PluralForms } from "@utils/i18n"
 
 const DISCOUNT_CAP = 50
 
@@ -7,6 +8,34 @@ const EXAMPLE_BADGES = 2
 
 type Part = string | { b: string }
 
+// ItemsHelper#item_form_wording — the same templates the server fills.
+interface Wording {
+  unlock_everyone: string
+  unlock_restricted: string
+  unlock_rank: string
+  unlock_badges: PluralForms
+  lives_yes: string
+  lives_no: string
+  no_discount: string
+  example: string
+  max: string
+  holder_rank: string
+  holder_badges: PluralForms
+  holder_all_badges: string
+  holder_join_and: string
+  holder_join_with: string
+  warn_cap: string
+  warn_rank_everyone: string
+  warn_rank_gate: string
+  warn_badge_required: string
+  discount_up_to: string
+  seal_rank: string
+  seal_badge: string
+  name_placeholder: string
+  rules_placeholder: string
+  buy: string
+}
+
 class ItemFormController extends Controller<HTMLFormElement> {
   static targets = [
     "name", "rules", "story", "price", "zero", "unlockRank", "discountRank",
@@ -27,6 +56,7 @@ class ItemFormController extends Controller<HTMLFormElement> {
     badgeNames: Array,
     exampleRankOrder: Array,
     exampleBadgeOrder: Array,
+    i18n: Object,
   }
 
   declare readonly ladderDiscountValue: number
@@ -35,6 +65,7 @@ class ItemFormController extends Controller<HTMLFormElement> {
   declare readonly badgeNamesValue: string[]
   declare readonly exampleRankOrderValue: string[]
   declare readonly exampleBadgeOrderValue: string[]
+  declare readonly i18nValue: Wording
 
   declare readonly nameTarget: HTMLInputElement
   declare readonly rulesTarget: HTMLTextAreaElement
@@ -98,27 +129,31 @@ class ItemFormController extends Controller<HTMLFormElement> {
     this.applyState()
   }
 
+  private get t(): Wording {
+    return this.i18nValue
+  }
+
   private renderCard() {
     const name = this.nameTarget.value.trim()
     const rules = this.rulesTarget.value.trim()
     const story = this.storyTarget.value.trim()
 
-    this.placeholder(this.frontNameTarget, name, "Nazwa przedmiotu")
-    this.placeholder(this.frontRulesTarget, rules, "Co daje studentowi…")
+    this.placeholder(this.frontNameTarget, name, this.t.name_placeholder)
+    this.placeholder(this.frontRulesTarget, rules, this.t.rules_placeholder)
 
     this.frontFlavorTarget.textContent = story
     this.frontFlavorTarget.hidden = story === ""
 
     this.frontCostTarget.textContent = String(this.price)
-    this.buyLabelTarget.textContent = `Kup za ${this.price}`
+    this.buyLabelTarget.textContent = interpolate(this.t.buy, { price: this.price })
     this.needTarget.textContent = String(Math.max(1, Math.ceil(this.price * 0.4)))
 
     const discount = this.maxDiscount
-    this.tagDiscTarget.textContent = `Zniżki do −${discount}%`
+    this.tagDiscTarget.textContent = interpolate(this.t.discount_up_to, { discount })
     this.tagDiscTarget.hidden = discount === 0
     this.tagLifeTarget.hidden = !this.zeroTarget.checked
 
-    this.thumbNameTarget.textContent = name || "Nazwa przedmiotu"
+    this.thumbNameTarget.textContent = name || this.t.name_placeholder
   }
 
   private renderRequirements() {
@@ -134,11 +169,8 @@ class ItemFormController extends Controller<HTMLFormElement> {
     this.reqListTarget.replaceChildren(...lines)
 
     const first = requirements[0]
-    this.sealLabelTarget.textContent = first
-      ? first.kind === "rank"
-        ? `Od rangi ${first.name}`
-        : `Za odznakę ${first.name}`
-      : ""
+    const seal = first?.kind === "rank" ? this.t.seal_rank : this.t.seal_badge
+    this.sealLabelTarget.textContent = first ? interpolate(seal, { name: first.name }) : ""
   }
 
   private renderSentences() {
@@ -222,28 +254,19 @@ class ItemFormController extends Controller<HTMLFormElement> {
     const gateIndex = this.unlockRankTarget.selectedIndex
 
     if (gate && floorIndex > 0 && gateIndex >= floorIndex) {
-      notes.push(
-        gates
-          ? `Kupić mogą tylko studenci od rangi ${gate}, więc zniżka dla rang obejmie każdego kupującego.`
-          : "Zniżka dla rang obejmie każdego kupującego.",
-      )
+      notes.push(gates ? interpolate(this.t.warn_rank_gate, { rank: gate }) : this.t.warn_rank_everyone)
     }
 
     const raw = this.rankDiscountReach.discount + this.badgeDiscountValue
     if (raw > DISCOUNT_CAP) {
-      notes.push(
-        `Zniżki sumują się do ${raw}%, a sklep odejmie najwyżej ${DISCOUNT_CAP}%. ` +
-          "Nadwyżka przepada — rozważ niższe zniżki przy rangach i odznakach.",
-      )
+      notes.push(interpolate(this.t.warn_cap, { raw, cap: DISCOUNT_CAP }))
     }
 
     const required = new Set(this.chosen(this.unlockBadgeTargets).map(({ name }) => name))
     this.chosen(this.discountBadgeTargets)
       .filter(({ name }) => required.has(name))
       .forEach(({ name }) => {
-        notes.push(
-          `Odznaka ${name} jest wymagana do zakupu, więc jej zniżka obejmie każdego kupującego.`,
-        )
+        notes.push(interpolate(this.t.warn_badge_required, { name }))
       })
 
     return notes
@@ -252,29 +275,29 @@ class ItemFormController extends Controller<HTMLFormElement> {
   private unlockParts(): Part[] {
     const rank = this.requirements.find(({ kind }) => kind === "rank")?.name ?? ""
     const badges = this.chosen(this.unlockBadgeTargets).map(({ name }) => name)
-    const tail = this.zeroTarget.checked
-      ? ". Także przy 0 życiach."
-      : ", jeśli mają co najmniej 1 życie."
+    const lives = this.zeroTarget.checked ? this.t.lives_yes : this.t.lives_no
 
     if (!rank && badges.length === 0) {
-      return ["Każdy student może kupić ten przedmiot", tail]
+      return fill(this.t.unlock_everyone, { lives })
     }
 
-    const parts: Part[] = ["Kupią tylko studenci"]
-    if (rank) parts.push(" z rangą ", { b: rank }, " lub wyższą")
-    if (badges.length > 0) {
-      parts.push(
-        `, którzy mają ${badges.length > 1 ? "wszystkie odznaki" : "odznakę"} `,
-        { b: andList(badges) },
-      )
-    }
-    parts.push(tail)
-    return parts
+    return fill(this.t.unlock_restricted, {
+      rank: rank ? fill(this.t.unlock_rank, { rank: { b: rank } }) : [],
+      badges: this.badgePhrase(this.t.unlock_badges, badges) ?? [],
+      lives,
+    })
+  }
+
+  // "odznaką X" / "odznakami X i Y" — a plural template filled with the names.
+  private badgePhrase(forms: PluralForms, names: string[]): Part[] | null {
+    if (names.length === 0) return null
+
+    return fill(pluralTemplate(forms, names.length), { badges: { b: andList(names) } })
   }
 
   private discountParts(): Part[] {
     if (this.maxDiscount === 0) {
-      return ["Bez zniżek. Każdy kupujący zapłaci ", { b: String(this.price) }, "."]
+      return fill(this.t.no_discount, { price: { b: String(this.price) } })
     }
 
     const { rank, badges, percent } = this.example
@@ -282,18 +305,14 @@ class ItemFormController extends Controller<HTMLFormElement> {
 
     const paid = Math.ceil((this.price * (100 - percent)) / 100)
 
-    const names = badges.map((badge) => badge.name)
-    const phrase: Part[] | null =
-      names.length === 0 ? null : [names.length > 1 ? "odznakami " : "odznaką ", { b: andList(names) }]
-    const parts: Part[] = ["Przykładowo: student", ...holderClause(rank, phrase)]
-    parts.push(
-      " zaoszczędzi ",
-      { b: `${percent}%` },
-      " i zapłaci ",
-      { b: String(paid) },
-      ` zamiast ${this.price}.`,
-    )
-    return parts
+    const phrase = this.badgePhrase(this.t.holder_badges, badges.map((badge) => badge.name))
+
+    return fill(this.t.example, {
+      holder: this.holderClause(rank, phrase),
+      percent: { b: `${percent}%` },
+      paid: { b: String(paid) },
+      price: String(this.price),
+    })
   }
 
   private maxParts(): Part[] {
@@ -302,11 +321,20 @@ class ItemFormController extends Controller<HTMLFormElement> {
 
     const reach = this.rankDiscountReach
     const badges = this.badgeNamesValue
-    const phrase: Part[] | null =
-      badges.length === 0 ? null : badges.length === 1 ? ["odznaką ", { b: badges[0] }] : ["wszystkimi odznakami"]
-    const clause = holderClause(reach.discount > 0 ? reach.name : "", phrase)
+    const phrase = badges.length > 1 ? [this.t.holder_all_badges] : this.badgePhrase(this.t.holder_badges, badges)
 
-    return ["Maksymalnie: student", ...clause, " uzyska zniżkę ", { b: `${percent}%` }, "."]
+    return fill(this.t.max, {
+      holder: this.holderClause(reach.discount > 0 ? reach.name : "", phrase),
+      percent: { b: `${percent}%` },
+    })
+  }
+
+  private holderClause(rankName: string, badgePhrase: Part[] | null): Part[] {
+    const rank = rankName ? fill(this.t.holder_rank, { rank: { b: rankName } }) : []
+    if (badgePhrase === null) return rank
+
+    const join = rankName ? this.t.holder_join_and : this.t.holder_join_with
+    return [...rank, ...fill(join, { phrase: badgePhrase })]
   }
 
   private get example(): { rank: string; badges: { name: string; discount: number }[]; percent: number } {
@@ -354,7 +382,7 @@ class ItemFormController extends Controller<HTMLFormElement> {
     }
 
     return picked
-      .sort((a, b) => a.localeCompare(b, "pl"))
+      .sort((a, b) => a.localeCompare(b, locale()))
       .map((name) => ({ name, discount: all.get(name) ?? 0 }))
   }
 
@@ -384,7 +412,7 @@ class ItemFormController extends Controller<HTMLFormElement> {
         name: chip.dataset.ghName ?? "",
         discount: parseInt(chip.dataset.ghDiscount ?? "0", 10) || 0,
       }))
-      .sort((a, b) => a.name.localeCompare(b.name, "pl"))
+      .sort((a, b) => a.name.localeCompare(b.name, locale()))
   }
 
   private selectedOption(select: HTMLSelectElement): HTMLOptionElement | undefined {
@@ -413,18 +441,18 @@ class ItemFormController extends Controller<HTMLFormElement> {
   }
 }
 
-function holderClause(rankName: string, badgePhrase: Part[] | null): Part[] {
-  const clause: Part[] = []
-  if (rankName) clause.push(" z rangą ", { b: rankName })
-  if (badgePhrase === null) return clause
-
-  return [...clause, rankName ? " oraz " : " z ", ...badgePhrase]
-}
+// The client twin of ApplicationHelper#gh_fill: splits a template on its
+// %{slots} and drops in plain text, bold names or already-built fragments.
+function fill(template: string, vars: Record<string, Part | Part[]>): Part[] {
+  return template.split(/(%\{\w+\})/).flatMap((piece): Part[] => {
+    const key = /^%\{(\w+)\}$/.exec(piece)?.[1]
+    if (key === undefined) return piece === "" ? [] : [piece]
 
-function andList(names: string[]): string {
-  if (names.length < 2) return names[0] ?? ""
+    const value = vars[key]
+    if (value === undefined) return [piece]
 
-  return `${names.slice(0, -1).join(", ")} i ${names[names.length - 1]}`
+    return Array.isArray(value) ? value : [value]
+  })
 }
 
 application.register("item-form", ItemFormController)
diff --git a/app/javascript/controllers/preset_row_controller.ts b/app/javascript/controllers/preset_row_controller.ts
index 3aa2c20d..37c4f5a6 100644
--- a/app/javascript/controllers/preset_row_controller.ts
+++ b/app/javascript/controllers/preset_row_controller.ts
@@ -1,17 +1,20 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { interpolate } from "@utils/i18n"
 
 class PresetRowController extends Controller<HTMLElement> {
   static targets = ["keep", "label", "icon"]
 
+  static values = { name: String, remove: String, restore: String }
+
   declare readonly keepTarget: HTMLInputElement
   declare readonly labelTarget: HTMLElement
   declare readonly iconTarget: HTMLElement
-
-  private name = ""
+  declare readonly nameValue: string
+  declare readonly removeValue: string
+  declare readonly restoreValue: string
 
   connect() {
-    this.name = this.labelTarget.textContent?.replace(/^\w+:\s*/u, "") ?? ""
     this.render()
   }
 
@@ -23,7 +26,7 @@ class PresetRowController extends Controller<HTMLElement> {
     const kept = this.keepTarget.checked
 
     this.element.classList.toggle("gh-preset-row--removed", !kept)
-    this.labelTarget.textContent = `${kept ? "Usuń" : "Przywróć"}: ${this.name}`
+    this.labelTarget.textContent = interpolate(kept ? this.removeValue : this.restoreValue, { name: this.nameValue })
     this.iconTarget.classList.toggle("fa-xmark", kept)
     this.iconTarget.classList.toggle("fa-rotate-left", !kept)
 
diff --git a/app/javascript/controllers/rank_form_controller.ts b/app/javascript/controllers/rank_form_controller.ts
index 6f8e3271..d5401b75 100644
--- a/app/javascript/controllers/rank_form_controller.ts
+++ b/app/javascript/controllers/rank_form_controller.ts
@@ -1,8 +1,31 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { interpolate, pluralize, type PluralForms } from "@utils/i18n"
 
 interface Rung { id: number | string; name: string; min: number; disc: number }
 
+interface Wording {
+  required: string
+  gives_discount: string
+  discount: string
+  starting: string
+  no_discount: string
+  name_placeholder: string
+  new_rank: string
+  from_short: string
+  impact_got_lead: string
+  impact_got: PluralForms
+  impact_got_tail: string
+  impact_nobody: string
+  impact_unchanged: string
+  impact_changed_lead: string
+  impact_changed: PluralForms
+  impact_up: string
+  impact_down: string
+  warn_below: string
+  warn_above: string
+}
+
 class RankFormController extends Controller<HTMLFormElement> {
   static targets = [
     "name", "threshold", "discount",
@@ -15,6 +38,7 @@ class RankFormController extends Controller<HTMLFormElement> {
     rungs: Array,
     totals: Array,
     editingId: Number,
+    i18n: Object,
   }
 
   declare readonly nameTarget: HTMLInputElement
@@ -33,6 +57,7 @@ class RankFormController extends Controller<HTMLFormElement> {
   declare readonly rungsValue: Rung[]
   declare readonly totalsValue: number[]
   declare readonly editingIdValue: number
+  declare readonly i18nValue: Wording
 
   connect() {
     this.refresh()
@@ -69,9 +94,9 @@ class RankFormController extends Controller<HTMLFormElement> {
   }
 
   private renderCard(draft: Rung) {
-    this.cardNameTarget.textContent = draft.name || "Nazwa rangi"
+    this.cardNameTarget.textContent = draft.name || this.i18nValue.name_placeholder
     this.cardNameTarget.classList.toggle("gh-placeholder-text", draft.name === "")
-    this.cardRulesTarget.textContent = rewardLine(draft)
+    this.cardRulesTarget.textContent = this.rewardLine(draft)
     this.renderArt()
   }
 
@@ -96,9 +121,9 @@ class RankFormController extends Controller<HTMLFormElement> {
   }
 
   private renderDraftRow(draft: Rung) {
-    this.draftNameTarget.textContent = draft.name || "Nowa ranga"
-    this.draftTermsTarget.textContent = ladderTerms(draft)
-    this.draftValueTarget.textContent = `od ${draft.min}`
+    this.draftNameTarget.textContent = draft.name || this.i18nValue.new_rank
+    this.draftTermsTarget.textContent = this.ladderTerms(draft)
+    this.draftValueTarget.textContent = interpolate(this.i18nValue.from_short, { min: draft.min })
     this.draftRow?.setAttribute("data-min", String(draft.min))
   }
 
@@ -127,18 +152,17 @@ class RankFormController extends Controller<HTMLFormElement> {
 
   private renderImpact(draft: Rung) {
     const { up, down, got } = this.impact(draft)
+    const t = this.i18nValue
 
     if (!this.editing) {
       if (got > 0) {
         this.impactTarget.replaceChildren(
-          text("Od razu dostanie ją "),
-          bold(`${got} ${plural(got, "student", "studentów", "studentów")}`),
-          text(". Pozostali zobaczą ją jako kolejny cel."),
+          text(t.impact_got_lead),
+          bold(pluralize(t.impact_got, got)),
+          text(t.impact_got_tail),
         )
       } else {
-        this.impactTarget.replaceChildren(
-          text("Na razie nikt nie ma tylu zebranych. Studenci zobaczą ją jako kolejny cel."),
-        )
+        this.impactTarget.replaceChildren(text(t.impact_nobody))
       }
 
       return
@@ -146,15 +170,18 @@ class RankFormController extends Controller<HTMLFormElement> {
 
     const moved = up + down
     if (moved === 0) {
-      this.impactTarget.replaceChildren(text("Żaden student nie zmieni rangi."))
+      this.impactTarget.replaceChildren(text(t.impact_unchanged))
       return
     }
 
-    const changes = [up && `${up} awansuje`, down && `${down} spadnie`].filter(Boolean)
+    const changes = [
+      up && interpolate(t.impact_up, { count: up }),
+      down && interpolate(t.impact_down, { count: down }),
+    ].filter(Boolean)
 
     this.impactTarget.replaceChildren(
-      text("Po zapisaniu "),
-      bold(`${moved} ${plural(moved, "student zmieni", "studentów zmieni", "studentów zmieni")} rangę`),
+      text(t.impact_changed_lead),
+      bold(pluralize(t.impact_changed, moved)),
       text(`: ${changes.join(", ")}.`),
     )
   }
@@ -187,20 +214,27 @@ class RankFormController extends Controller<HTMLFormElement> {
     const messages: string[] = []
 
     if (below && draft.disc < below.disc) {
-      messages.push(
-        `Ranga niżej (${below.name}) daje −${below.disc}%, a ta tylko −${draft.disc}%. ` +
-        "Awans obniżyłby zniżkę.",
-      )
+      messages.push(interpolate(this.i18nValue.warn_below, { name: below.name, other: below.disc, discount: draft.disc }))
     }
 
     if (above && draft.disc > above.disc) {
-      messages.push(
-        `Ranga wyżej (${above.name}) daje tylko −${above.disc}%. Awans na nią obniżyłby zniżkę.`,
-      )
+      messages.push(interpolate(this.i18nValue.warn_above, { name: above.name, other: above.disc }))
     }
 
     this.warningsTarget.replaceChildren(...messages.map(warning))
   }
+
+  private rewardLine(rung: Rung): string {
+    const line = interpolate(this.i18nValue.required, { min: rung.min })
+
+    return rung.disc > 0 ? `${line} ${interpolate(this.i18nValue.gives_discount, { discount: rung.disc })}` : line
+  }
+
+  private ladderTerms(rung: Rung): string {
+    if (rung.disc > 0) return interpolate(this.i18nValue.discount, { discount: rung.disc })
+
+    return rung.min === 0 ? this.i18nValue.starting : this.i18nValue.no_discount
+  }
 }
 
 function numberIn(input: HTMLInputElement): number {
@@ -218,29 +252,6 @@ function held(total: number, ladder: Rung[]): Rung | null {
   )
 }
 
-function rewardLine(rung: Rung): string {
-  const line = `Wymagane: ${rung.min} zebranych.`
-
-  return rung.disc > 0 ? `${line} Daje −${rung.disc}% w sklepie.` : line
-}
-
-function ladderTerms(rung: Rung): string {
-  if (rung.disc > 0) return `−${rung.disc}% w sklepie`
-
-  return rung.min === 0 ? "Ranga startowa" : "Bez zniżki"
-}
-
-function plural(count: number, one: string, few: string, many: string): string {
-  const n = Math.abs(count)
-  const lastTwo = n % 100
-  const lastOne = n % 10
-
-  if (n === 1) return one
-  if (lastOne >= 2 && lastOne <= 4 && (lastTwo < 12 || lastTwo > 14)) return few
-
-  return many
-}
-
 function text(value: string): Text {
   return document.createTextNode(value)
 }
diff --git a/app/javascript/controllers/sheet_create_controller.ts b/app/javascript/controllers/sheet_create_controller.ts
index 60735464..2464b0b9 100644
--- a/app/javascript/controllers/sheet_create_controller.ts
+++ b/app/javascript/controllers/sheet_create_controller.ts
@@ -1,5 +1,11 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { pluralize, type PluralForms } from "@utils/i18n"
+
+interface Wording {
+  create_one: string
+  create_many: PluralForms
+}
 
 class SheetCreateController extends Controller<HTMLElement> {
   static targets = [
@@ -7,7 +13,7 @@ class SheetCreateController extends Controller<HTMLElement> {
   ]
 
   static values = {
-    sheets: Array,
+    i18n: Object,
     min: { type: Number, default: 2 },
   }
 
@@ -20,7 +26,7 @@ class SheetCreateController extends Controller<HTMLElement> {
   declare readonly downTarget: HTMLButtonElement
   declare readonly nameTargets: HTMLElement[]
   declare readonly submitLabelTarget: HTMLElement
-  declare readonly sheetsValue: string[]
+  declare readonly i18nValue: Wording
   declare readonly minValue: number
 
   connect() {
@@ -42,9 +48,7 @@ class SheetCreateController extends Controller<HTMLElement> {
       chip.hidden = index >= count
     })
 
-    this.submitLabelTarget.textContent = many
-      ? `Utwórz ${count} ${plural(count, this.sheetsValue)}`
-      : `Utwórz ${plural(1, this.sheetsValue)}`
+    this.submitLabelTarget.textContent = many ? pluralize(this.i18nValue.create_many, count) : this.i18nValue.create_one
   }
 
   up() {
@@ -77,15 +81,4 @@ class SheetCreateController extends Controller<HTMLElement> {
   }
 }
 
-function plural(count: number, forms: string[]): string {
-  const [one, few, many] = forms
-  const last = count % 10
-  const teens = count % 100
-
-  if (count === 1) return one
-  if (last >= 2 && last <= 4 && (teens < 12 || teens > 14)) return few
-
-  return many
-}
-
 application.register("sheet-create", SheetCreateController)
diff --git a/app/javascript/controllers/sheet_form_controller.ts b/app/javascript/controllers/sheet_form_controller.ts
index 9077c584..43d5c567 100644
--- a/app/javascript/controllers/sheet_form_controller.ts
+++ b/app/javascript/controllers/sheet_form_controller.ts
@@ -1,5 +1,17 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { interpolate, pluralize, type PluralForms } from "@utils/i18n"
+
+interface Wording {
+  columns: PluralForms
+  dirty: string
+  clean: string
+  name_label: string
+  reward_label: string
+  story_label: string
+  destroy_column: string
+  destroy_category: string
+}
 
 class SheetFormController extends Controller<HTMLElement> {
   static targets = [
@@ -10,9 +22,8 @@ class SheetFormController extends Controller<HTMLElement> {
   ]
 
   static values = {
-    columns: Array,
-    currency: String,
-    categoryLabel: String,
+    i18n: Object,
+    sheet: Boolean,
     editing: String,
   }
 
@@ -30,9 +41,8 @@ class SheetFormController extends Controller<HTMLElement> {
   declare readonly previewRowTargets: HTMLElement[]
   declare readonly previewHeadCellTarget: HTMLTemplateElement
   declare readonly previewBodyCellTarget: HTMLTemplateElement
-  declare readonly columnsValue: string[]
-  declare readonly currencyValue: string
-  declare readonly categoryLabelValue: string
+  declare readonly i18nValue: Wording
+  declare readonly sheetValue: boolean
   declare readonly editingValue: string
 
   private destination = ""
@@ -167,7 +177,7 @@ class SheetFormController extends Controller<HTMLElement> {
     const count = columns.length
     const max = columns.reduce((total, row) => total + this.reward(row), 0)
 
-    this.summaryCountTarget.textContent = `${count} ${plural(count, this.columnsValue)}`
+    this.summaryCountTarget.textContent = pluralize(this.i18nValue.columns, count)
     this.summaryMaxTarget.textContent = String(max)
   }
 
@@ -176,7 +186,7 @@ class SheetFormController extends Controller<HTMLElement> {
 
     const dirty = this.dirty
 
-    this.dirtyTarget.textContent = dirty ? "Niezapisane zmiany" : "Brak zmian"
+    this.dirtyTarget.textContent = dirty ? this.i18nValue.dirty : this.i18nValue.clean
     this.submitTarget.disabled = !dirty
   }
 
@@ -189,12 +199,14 @@ class SheetFormController extends Controller<HTMLElement> {
       const position = row.querySelector<HTMLInputElement>("[data-sheet-form-target='position']")
       if (position) position.value = String(number - 1)
 
-      this.relabel(row, "name", `Kategoria ${number}: za co`)
-      this.relabel(row, "reward", `Nagroda za kategorię ${number}`)
-      this.relabel(row, "destroy", `Usuń ${this.categoryLabelValue} ${number}`)
+      const t = this.i18nValue
+
+      this.relabel(row, "name", interpolate(t.name_label, { number }))
+      this.relabel(row, "reward", interpolate(t.reward_label, { number }))
+      this.relabel(row, "destroy", interpolate(this.sheetValue ? t.destroy_column : t.destroy_category, { number }))
 
       const story = row.querySelector<HTMLElement>("textarea")
-      story?.setAttribute("aria-label", `Opis fabularny kategorii ${number}`)
+      story?.setAttribute("aria-label", interpolate(t.story_label, { number }))
     })
 
     const rows = this.liveRows
@@ -269,15 +281,4 @@ class SheetFormController extends Controller<HTMLElement> {
   }
 }
 
-function plural(count: number, forms: string[]): string {
-  const [one, few, many] = forms
-  const last = count % 10
-  const teens = count % 100
-
-  if (count === 1) return one
-  if (last >= 2 && last <= 4 && (teens < 12 || teens > 14)) return few
-
-  return many
-}
-
 application.register("sheet-form", SheetFormController)
diff --git a/app/javascript/controllers/sidebar_controller.ts b/app/javascript/controllers/sidebar_controller.ts
index e0af28e5..0934ed5d 100644
--- a/app/javascript/controllers/sidebar_controller.ts
+++ b/app/javascript/controllers/sidebar_controller.ts
@@ -5,8 +5,8 @@ class SidebarController extends Controller {
   static targets = ["sidebar", "label", "icon"]
   static values = {
     cookie: { type: String, default: "sidebar_collapsed" },
-    expandLabel: { type: String, default: "Rozwiń" },
-    collapseLabel: { type: String, default: "Zwiń panel" },
+    expandLabel: String,
+    collapseLabel: String,
   }
 
   declare readonly sidebarTarget: HTMLElement
diff --git a/app/javascript/controllers/teacher_picker_controller.ts b/app/javascript/controllers/teacher_picker_controller.ts
index 7f5abfa5..cb79e9f0 100644
--- a/app/javascript/controllers/teacher_picker_controller.ts
+++ b/app/javascript/controllers/teacher_picker_controller.ts
@@ -1,15 +1,19 @@
 import { application } from "@controllers/application"
 import { Controller } from "@hotwired/stimulus"
+import { interpolate, pluralize, type PluralForms } from "@utils/i18n"
+
+interface Wording {
+  results: PluralForms
+  overflow: string
+  query: string
+}
 
 class TeacherPickerController extends Controller<HTMLFormElement> {
   static targets = ["input", "row", "name", "count", "hint", "results", "overflow", "empty", "emptyQuery"]
   static values = {
     min: { type: Number, default: 2 },
     max: { type: Number, default: 8 },
-    one: String,
-    few: String,
-    many: String,
-    overflow: String,
+    i18n: Object,
   }
 
   declare readonly inputTarget: HTMLInputElement
@@ -22,10 +26,7 @@ class TeacherPickerController extends Controller<HTMLFormElement> {
   declare readonly emptyQueryTarget: HTMLElement
   declare readonly minValue: number
   declare readonly maxValue: number
-  declare readonly oneValue: string
-  declare readonly fewValue: string
-  declare readonly manyValue: string
-  declare readonly overflowValue: string
+  declare readonly i18nValue: Wording
 
   noSubmit(event: KeyboardEvent) {
     event.preventDefault()
@@ -46,7 +47,7 @@ class TeacherPickerController extends Controller<HTMLFormElement> {
 
     if (hits.length === 0) {
       this.rowTargets.forEach((row) => this.plain(row))
-      this.emptyQueryTarget.textContent = `„${typed}”.`
+      this.emptyQueryTarget.textContent = interpolate(this.i18nValue.query, { query: typed })
       this.show({ empty: true })
 
       return
@@ -62,7 +63,9 @@ class TeacherPickerController extends Controller<HTMLFormElement> {
 
     const over = hits.length > this.maxValue
 
-    this.countTarget.textContent = `${hits.length} ${this.plural(hits.length)}${over ? this.overflowValue : ""}`
+    const overflow = over ? interpolate(this.i18nValue.overflow, { max: this.maxValue }) : ""
+
+    this.countTarget.textContent = `${pluralize(this.i18nValue.results, hits.length)}${overflow}`
     this.show({ count: true, results: true, overflow: over })
   }
 
@@ -102,17 +105,6 @@ class TeacherPickerController extends Controller<HTMLFormElement> {
     this.resultsTarget.hidden = !state.results
     this.overflowTarget.hidden = !state.overflow
   }
-
-  private plural(count: number): string {
-    const n = Math.abs(count)
-
-    if (n === 1) return this.oneValue
-
-    const lastOne = n % 10
-    const lastTwo = n % 100
-
-    return lastOne >= 2 && lastOne <= 4 && (lastTwo < 12 || lastTwo > 14) ? this.fewValue : this.manyValue
-  }
 }
 
 function fold(text: string): string {
diff --git a/app/javascript/utils/i18n.ts b/app/javascript/utils/i18n.ts
new file mode 100644
index 00000000..3937928c
--- /dev/null
+++ b/app/javascript/utils/i18n.ts
@@ -0,0 +1,34 @@
+// Client-side halves of Rails I18n. The wording itself always comes from the
+// view (config/locales/**), passed in as a Stimulus value; these only fill it in.
+
+// A pluralised key as Rails returns it when called without `count:` —
+// pl has one/few/many/other, en has one/other.
+export type PluralForms = Partial<Record<Intl.LDMLPluralRule, string>>
+
+type Vars = Record<string, string | number>
+
+// The page's language, set on <html lang> by the Localization concern.
+export function locale(): string {
+  return document.documentElement.lang || "pl"
+}
+
+// "%{name} ma %{count}" + { name: "Ala", count: 3 } -> "Ala ma 3".
+export function interpolate(template: string, vars: Vars = {}): string {
+  return template.replace(/%\{(\w+)\}/g, (match, key: string) => (key in vars ? String(vars[key]) : match))
+}
+
+// The form for `count`, unfilled — the same rule rails-i18n applies on the server.
+export function pluralTemplate(forms: PluralForms, count: number): string {
+  const rule = new Intl.PluralRules(locale()).select(count)
+
+  return forms[rule] ?? forms.other ?? ""
+}
+
+export function pluralize(forms: PluralForms, count: number, vars: Vars = {}): string {
+  return interpolate(pluralTemplate(forms, count), { count, ...vars })
+}
+
+// "a, b i c" / "a, b, and c" — matches Array#to_sentence with rails-i18n.
+export function andList(names: string[]): string {
+  return new Intl.ListFormat(locale(), { type: "conjunction" }).format(names)
+}
diff --git a/app/mailers/invitation_mailer.rb b/app/mailers/invitation_mailer.rb
index 28a3e886..f27b29b3 100644
--- a/app/mailers/invitation_mailer.rb
+++ b/app/mailers/invitation_mailer.rb
@@ -1,17 +1,13 @@
 # frozen_string_literal: true
 
 class InvitationMailer < ApplicationMailer
-  ROLE_LABELS = {
-    admin:  'administrator',
-    member: 'członek',
-  }.freeze
-
   def invitation_email
     @token_link = params[:token_link]
     @email = params[:email]
     @organization_name = params[:organization_name]
-    @role_label = ROLE_LABELS[params[:role]]
+    @role_label = t("invitation_mailer.roles.#{params[:role]}")
 
-    mail to: @email, subject: 'Zaproszenie do systemu GamificationHub'
+    # Subject: invitation_mailer.invitation_email.subject (default_i18n_subject).
+    mail to: @email
   end
 end
diff --git a/app/mailers/passwordless_mailer.rb b/app/mailers/passwordless_mailer.rb
index 1609e469..797a643e 100644
--- a/app/mailers/passwordless_mailer.rb
+++ b/app/mailers/passwordless_mailer.rb
@@ -9,6 +9,7 @@ def token_email
     @first_name          = params[:user_name].to_s.split(' ').first
     @expires_in_minutes  = LoginToken::EXPIRES_IN.in_minutes.to_i
 
-    mail to: @email, subject: 'Logowanie do systemu Gamification Hub'
+    # Subject: passwordless_mailer.token_email.subject (default_i18n_subject).
+    mail to: @email
   end
 end
diff --git a/app/models/activity_group.rb b/app/models/activity_group.rb
index 09dc9e05..dbd97927 100644
--- a/app/models/activity_group.rb
+++ b/app/models/activity_group.rb
@@ -10,7 +10,7 @@ class ActivityGroup < ApplicationRecord
 
   accepts_nested_attributes_for :activity_group_categories, allow_destroy: true
 
-  validates :name, presence: { message: 'Podaj nazwę arkusza.' }, length: { maximum: 100 }
+  validates :name, presence: true, length: { maximum: 100 }
   validate :at_least_one_visible_category, on: :settings
 
   scope :newest_first, -> { order(created_at: :desc, id: :desc) }
@@ -51,6 +51,6 @@ def next_number_for_base(template)
   def at_least_one_visible_category
     return if activity_group_categories.any? { |category| !category.marked_for_destruction? && !category.hidden? }
 
-    errors.add(:base, 'Dodaj co najmniej jedną widoczną kategorię.')
+    errors.add(:base, :no_visible_category)
   end
 end
diff --git a/app/models/activity_group_template.rb b/app/models/activity_group_template.rb
index 192322f3..15a97cdf 100644
--- a/app/models/activity_group_template.rb
+++ b/app/models/activity_group_template.rb
@@ -9,7 +9,7 @@ class ActivityGroupTemplate < ApplicationRecord
 
   accepts_nested_attributes_for :categories, allow_destroy: true
 
-  validates :base_name, presence: { message: 'Podaj nazwę szablonu.' }, length: { maximum: 100 }
+  validates :base_name, presence: true, length: { maximum: 100 }
   validate :at_least_one_category, on: :settings
 
   scope :newest_first, -> { order(created_at: :desc, id: :desc) }
@@ -21,6 +21,6 @@ def max_reward = categories.sum { |category| category.reward.to_i }
   def at_least_one_category
     return if categories.any? { |category| !category.marked_for_destruction? }
 
-    errors.add(:base, 'Dodaj co najmniej jedną widoczną kategorię.')
+    errors.add(:base, :no_category)
   end
 end
diff --git a/app/models/badge.rb b/app/models/badge.rb
index 68e6ae7b..bf5cce44 100644
--- a/app/models/badge.rb
+++ b/app/models/badge.rb
@@ -10,18 +10,16 @@ class Badge < ApplicationRecord
 
   has_icon_art :icon, glyphs: Glyphs::BADGE
 
-  validates :name, presence: { message: 'Podaj nazwę odznaki.' },
-                   length:   { maximum: 50 }
+  validates :name, presence: true, length: { maximum: 50 }
 
-  validates :didactic_description, presence: { message: 'Napisz, jak zdobyć tę odznakę.' },
-                                   length:   { maximum: 255 }
+  validates :didactic_description, presence: true, length: { maximum: 255 }
 
   validates :story_description, length: { maximum: 255 }
 
   validates :discount, numericality: {
     greater_than_or_equal_to: 0,
     less_than_or_equal_to:    100,
-    message:                  'Zniżka musi mieścić się między 0 a 100%.',
+    message:                  :out_of_range,
   }
 
   scope :by_name, -> { order(:name, :id) }
diff --git a/app/models/concerns/iconable.rb b/app/models/concerns/iconable.rb
index 5350e46f..82f1f6fe 100644
--- a/app/models/concerns/iconable.rb
+++ b/app/models/concerns/iconable.rb
@@ -6,7 +6,7 @@ module Iconable
   ACCEPTABLE_ICON_TYPES = ['image/gif', 'image/jpeg', 'image/png'].freeze
 
   class_methods do
-    def has_icon_art(attribute, glyphs:, glyph_message: 'Nieznana grafika.', required: true)
+    def has_icon_art(attribute, glyphs:, glyph_message: :unknown_art, required: true)
       has_one_attached attribute
 
       glyph_attribute      = :"#{attribute}_glyph"
@@ -41,7 +41,7 @@ def define_icon_content_type_validator(validator_name, attribute)
         next unless attachment.attached?
         next if Iconable::ACCEPTABLE_ICON_TYPES.include?(attachment.content_type)
 
-        errors.add(attribute, 'Grafika musi być plikiem GIF, JPG lub PNG.')
+        errors.add(attribute, :art_type)
       end
     end
 
@@ -49,7 +49,7 @@ def define_icon_art_chosen_validator(validator_name, attribute, glyph_attribute)
       define_method(validator_name) do
         next if public_send(glyph_attribute).present? || public_send(attribute).attached?
 
-        errors.add(glyph_attribute, 'Wybierz gotową grafikę albo wgraj własną.')
+        errors.add(glyph_attribute, :art_missing)
       end
     end
 
diff --git a/app/models/concerns/reward_category.rb b/app/models/concerns/reward_category.rb
index 8d1e93ee..9886685b 100644
--- a/app/models/concerns/reward_category.rb
+++ b/app/models/concerns/reward_category.rb
@@ -6,12 +6,12 @@ module RewardCategory
   included do
     default_scope { order(position: :asc) }
 
-    validates :didactic_description, presence: { message: 'Podaj, za co jest nagroda.' }
+    validates :didactic_description, presence: true
     validates :reward,
               numericality: {
                 only_integer:             true,
                 greater_than_or_equal_to: 1,
-                message:                  'Nagroda musi wynosić co najmniej 1.',
+                message:                  :too_low,
               }
   end
 end
diff --git a/app/models/item.rb b/app/models/item.rb
index 12839098..8940f241 100644
--- a/app/models/item.rb
+++ b/app/models/item.rb
@@ -17,21 +17,20 @@ class Item < ApplicationRecord
   has_many :discount_badges, through: :items_min_badges_for_discounts, source: :badge
 
   has_many :students_items, dependent: :destroy
+  has_many :notifications, dependent: :destroy
 
   has_icon_art :icon, glyphs: Glyphs::ITEM
 
-  validates :name, presence: { message: 'Podaj nazwę przedmiotu.' },
-                   length:   { maximum: 50 }
+  validates :name, presence: true, length: { maximum: 50 }
 
-  validates :didactic_description, presence: { message: 'Napisz, co przedmiot daje studentowi.' },
-                                   length:   { maximum: 255 }
+  validates :didactic_description, presence: true, length: { maximum: 255 }
 
   validates :story_description, length: { maximum: 255 }
 
   validates :price, numericality: {
     only_integer:             true,
     greater_than_or_equal_to: 1,
-    message:                  'Cena musi wynosić co najmniej 1.',
+    message:                  :too_low,
   }
 
   scope :by_price, -> { order(:price, :name, :id) }
diff --git a/app/models/organization.rb b/app/models/organization.rb
index 0e226bc3..efabda32 100644
--- a/app/models/organization.rb
+++ b/app/models/organization.rb
@@ -34,13 +34,13 @@ def max_members_not_below_members_count
     members_count = users.count
     return if max_members >= members_count
 
-    errors.add(:max_members, "can't be lower than the current number of members (#{members_count})")
+    errors.add(:max_members, :below_members, count: members_count)
   end
 
   def keep_usos_organization
     return unless usos?
 
-    errors.add(:base, 'Organizacji powiązanej z USOS nie można usunąć.')
+    errors.add(:base, :usos_undeletable)
     throw :abort
   end
 end
diff --git a/app/models/rank.rb b/app/models/rank.rb
index e08cd720..de8917e3 100644
--- a/app/models/rank.rb
+++ b/app/models/rank.rb
@@ -7,19 +7,18 @@ class Rank < ApplicationRecord
 
   has_icon_art :icon, glyphs: Glyphs::RANK
 
-  validates :name, presence: { message: 'Podaj nazwę rangi.' },
-                   length:   { maximum: 40 }
+  validates :name, presence: true, length: { maximum: 40 }
 
   validates :discount, numericality: {
     greater_than_or_equal_to: 0,
     less_than_or_equal_to:    100,
-    message:                  'Zniżka musi mieścić się między 0 a 100%.',
+    message:                  :out_of_range,
   }
 
   validates :required_currency_value, numericality: {
     only_integer:             true,
     greater_than_or_equal_to: 0,
-    message:                  'Próg nie może być ujemny.',
+    message:                  :negative,
   }
 
   validate :threshold_free_in_group
@@ -34,8 +33,8 @@ def threshold_free_in_group
                        .first
     return if clash.nil?
 
-    errors.add(:required_currency_value,
-               "Ranga #{clash.name} ma już próg #{clash.required_currency_value}. Wybierz inny.",)
+    errors.add(:required_currency_value, :threshold_taken,
+               rank: clash.name, threshold: clash.required_currency_value,)
   end
 
   def starting?
diff --git a/app/models/story_group.rb b/app/models/story_group.rb
index 13d98ee2..34f35b47 100644
--- a/app/models/story_group.rb
+++ b/app/models/story_group.rb
@@ -5,10 +5,9 @@ class StoryGroup < ApplicationRecord
 
   enum :ranking_mode, { podium_and_own: 0, full: 1 }, prefix: :ranking
 
-  RANKING_MODE_LABELS = {
-    'podium_and_own' => 'Podium i własne miejsce',
-    'full'           => 'Pełny ranking',
-  }.freeze
+  class << self
+    def ranking_mode_label(mode) = I18n.t("story_groups.ranking_modes.#{mode}")
+  end
 
   belongs_to :owner, class_name: 'User', foreign_key: 'owner_id'
   has_many :notifications, dependent: :destroy
@@ -24,20 +23,18 @@ class StoryGroup < ApplicationRecord
   has_many :invites, class_name: 'StoryGroupInvite', foreign_key: 'story_group_id', dependent: :destroy
 
   has_icon_art :icon, glyphs: GroupArt::KEYS, required: false
-  has_icon_art :currency_icon, glyphs: CurrencyIcons::KEYS, glyph_message: 'Nieznana ikona.', required: false
+  has_icon_art :currency_icon, glyphs: CurrencyIcons::KEYS, glyph_message: :unknown_icon, required: false
 
-  validates :name, presence: { message: 'Podaj nazwę grupy.' },
-                   length:   { maximum: 40 }
-  validates :currency_name, presence: { message: 'Podaj nazwę waluty.' },
-                            length:   { maximum: 40 }
+  validates :name, presence: true, length: { maximum: 40 }
+  validates :currency_name, presence: true, length: { maximum: 40 }
   validates :description, length: { maximum: 1024 }
   validates :default_lives, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
 
   delegate :organization, to: :owner
 
   def ranking_summary
-    return 'Wyłączony' unless ranking_enabled?
+    return I18n.t('story_groups.ranking_off') unless ranking_enabled?
 
-    RANKING_MODE_LABELS.fetch(ranking_mode, ranking_mode)
+    self.class.ranking_mode_label(ranking_mode)
   end
 end
diff --git a/app/models/story_group_invite.rb b/app/models/story_group_invite.rb
index b92e9896..957767b3 100644
--- a/app/models/story_group_invite.rb
+++ b/app/models/story_group_invite.rb
@@ -1,18 +1,10 @@
 # frozen_string_literal: true
 
 class StoryGroupInvite < ApplicationRecord
-  include ApplicationHelper
-
   CODE_LENGTH = 6
 
   CODE_ALPHABET = 'ABCDEFGHJKMNPQRSTUVWXYZ23456789'
 
-  STATUS_LABELS = {
-    active:    'Aktywne',
-    expired:   'Wygasło',
-    exhausted: 'Wyczerpane',
-  }.freeze
-
   before_create :generate_code
 
   belongs_to :story_group
@@ -24,7 +16,7 @@ class StoryGroupInvite < ApplicationRecord
             numericality: {
               only_integer:             true,
               greater_than_or_equal_to: 1,
-              message:                  'Limit musi wynosić co najmniej 1.',
+              message:                  :too_low,
             },
             allow_nil:    true
 
@@ -73,7 +65,7 @@ def status
 
   def active? = status == :active
 
-  def status_label = STATUS_LABELS[status]
+  def status_label = I18n.t("story_group_invites.statuses.#{status}")
 
   def use!
     return unless usable?
@@ -86,10 +78,6 @@ def use!
   def max_uses_covers_existing_uses
     return if max_uses.blank? || uses.to_i.zero? || max_uses >= uses
 
-    errors.add(
-      :max_uses,
-      "Z tego kodu skorzystało już #{uses} #{gh_plural(uses, 'osoba', 'osoby', 'osób')}. " \
-      'Limit nie może być mniejszy.',
-    )
+    errors.add(:max_uses, :below_uses, count: uses)
   end
 end
diff --git a/app/models/story_group_student.rb b/app/models/story_group_student.rb
index dce4cd5d..e7f7ac1c 100644
--- a/app/models/story_group_student.rb
+++ b/app/models/story_group_student.rb
@@ -23,11 +23,10 @@ class StoryGroupStudent < ApplicationRecord
 
 
   validates :nickname,
-            length:      { in: 2..24, message: 'Pseudonim musi mieć od 2 do 24 znaków.' },
+            length:      { in: 2..24, message: :length },
             uniqueness:  {
               scope:          :story_group_id,
               case_sensitive: false,
-              message:        'Ten pseudonim jest już zajęty w tej grupie.',
             },
             allow_blank: true
 
diff --git a/app/models/story_group_teacher.rb b/app/models/story_group_teacher.rb
index c49ac518..1b18c63b 100644
--- a/app/models/story_group_teacher.rb
+++ b/app/models/story_group_teacher.rb
@@ -7,5 +7,5 @@ class StoryGroupTeacher < ApplicationRecord
   delegate :full_name, :university_number, :email, to: :user
   scope :with_user, -> { includes(:user) }
 
-  validates :user_id, uniqueness: { scope: :story_group_id, message: 'Ta osoba jest już w grupie.' }
+  validates :user_id, uniqueness: { scope: :story_group_id }
 end
diff --git a/app/models/user.rb b/app/models/user.rb
index 06a79fbd..f0edfad4 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -65,6 +65,6 @@ def consume_login_token!
   private
 
   def organization_has_free_slot
-    errors.add(:organization, 'has reached its member limit') if organization&.full?
+    errors.add(:organization, :member_limit) if organization&.full?
   end
 end
diff --git a/app/services/currency_adjustment_form.rb b/app/services/currency_adjustment_form.rb
index 406de213..db7c9f44 100644
--- a/app/services/currency_adjustment_form.rb
+++ b/app/services/currency_adjustment_form.rb
@@ -59,11 +59,11 @@ def validate
     errors.clear
 
     if value.nil?
-      errors.add(:amount, 'Podaj kwotę.')
+      errors.add(:amount, :missing)
     elsif value.zero?
-      errors.add(:amount, 'Podaj kwotę większą od zera.')
+      errors.add(:amount, :not_positive)
     elsif new_balance.negative?
-      errors.add(:amount, "Student ma tylko #{balance} do wydania.")
+      errors.add(:amount, :overdrawn, balance: balance)
     end
 
     errors.empty?
diff --git a/app/services/currency_ledger.rb b/app/services/currency_ledger.rb
index 4c88bd61..eb229ac0 100644
--- a/app/services/currency_ledger.rb
+++ b/app/services/currency_ledger.rb
@@ -2,14 +2,7 @@
 
 class CurrencyLedger
   # The filter chips, in the order they are shown. `nil` is "Wszystkie".
-  # Plural, unlike LedgerEntry::KIND_LABELS — a chip names a set of rows, a
-  # chip on a row names one.
-  KINDS = [
-    [nil, 'Wszystkie'],
-    %w[reward Nagrody],
-    %w[purchase Zakupy],
-    %w[adjustment Korekty],
-  ].freeze
+  KINDS = [nil, 'reward', 'purchase', 'adjustment'].freeze
 
   def initialize(student:)
     @student = student
@@ -76,11 +69,15 @@ def build_entry(transaction, running)
   def title_for(transaction, subject)
     case subject
     when Item                  then subject.name
-    when ActivityGroupCategory then subject.didactic_description.presence || 'Nagroda'
-    else                            transaction.reward? ? 'Nagroda' : 'Korekta waluty'
+    when ActivityGroupCategory then subject.didactic_description.presence || entry_title(:reward)
+    else                            entry_title(transaction.reward? ? :reward : :adjustment)
     end
   end
 
+  def entry_title(key)
+    I18n.t("currency_transactions.entry_titles.#{key}")
+  end
+
   # The second, smaller line. It answers "where did this come from" — the
   # sheet for a reward, the teacher for a correction. A purchase needs none:
   # the item name above it is the whole answer.
diff --git a/app/services/dashboard/global_admin.rb b/app/services/dashboard/global_admin.rb
index fd77c8d6..50cc452d 100644
--- a/app/services/dashboard/global_admin.rb
+++ b/app/services/dashboard/global_admin.rb
@@ -22,10 +22,10 @@ def to_partial_path = 'home/global_admin_start'
 
   def stat_tiles
     [
-      Dashboard::Tile.new(label: 'Organizacje', value: organizations.size, note: nil),
-      Dashboard::Tile.new(label: 'Konta w organizacjach', value: organizations.sum(&:member_count), note: nil),
-      Dashboard::Tile.new(label: 'Wolne miejsca', value: organizations.sum { |org| org.free.to_i }, note: nil),
-      Dashboard::Tile.new(label: 'Niezaakceptowane zaproszenia', value: organizations.sum(&:pending_admins), note: nil),
+      Dashboard::Tile.new(label: tile_label(:organizations), value: organizations.size, note: nil),
+      Dashboard::Tile.new(label: tile_label(:accounts), value: organizations.sum(&:member_count), note: nil),
+      Dashboard::Tile.new(label: tile_label(:free), value: organizations.sum { |org| org.free.to_i }, note: nil),
+      Dashboard::Tile.new(label: tile_label(:pending), value: organizations.sum(&:pending_admins), note: nil),
     ]
   end
 
@@ -35,6 +35,10 @@ def attention? = without_admin.any? || nearly_full.any?
 
   private
 
+  def tile_label(key)
+    I18n.t("home.global_admin_start.tiles.#{key}")
+  end
+
   def build_organizations
     organizations = Organization.order(:name).to_a
     users   = User.where(organization: organizations).group(:organization_id)
diff --git a/app/services/dashboard/organization_admin.rb b/app/services/dashboard/organization_admin.rb
index 825fa4e2..442f9343 100644
--- a/app/services/dashboard/organization_admin.rb
+++ b/app/services/dashboard/organization_admin.rb
@@ -27,19 +27,24 @@ def to_partial_path = 'home/organization_admin_start'
 
   def stat_tiles
     [
-      Dashboard::Tile.new(label: 'Studenci', value: @counts.fetch('student', 0), note: nil),
-      Dashboard::Tile.new(label: 'Nauczyciele', value: @counts.fetch('teacher', 0), note: nil),
+      Dashboard::Tile.new(label: tile_text(:students), value: @counts.fetch('student', 0), note: nil),
+      Dashboard::Tile.new(label: tile_text(:teachers), value: @counts.fetch('teacher', 0), note: nil),
       free_tile,
-      Dashboard::Tile.new(label: 'Oczekujące zaproszenia', value: pending_users.size, note: nil),
+      Dashboard::Tile.new(label: tile_text(:pending), value: pending_users.size, note: nil),
     ]
   end
 
   private
 
   def free_tile
-    return Dashboard::Tile.new(label: 'Wolne miejsca', value: 'Bez limitu', note: nil) if unlimited?
+    return Dashboard::Tile.new(label: tile_text(:free), value: tile_text(:no_limit), note: nil) if unlimited?
 
-    Dashboard::Tile.new(label: 'Wolne miejsca', value: free, note: "z #{organization.max_members}")
+    Dashboard::Tile.new(label: tile_text(:free), value: free,
+                        note:  tile_text(:of_max, max: organization.max_members),)
+  end
+
+  def tile_text(key, **)
+    I18n.t("home.organization_admin_start.tiles.#{key}", **)
   end
 
   def invitable
diff --git a/app/services/dashboard/teacher.rb b/app/services/dashboard/teacher.rb
index 71b76912..98cbed25 100644
--- a/app/services/dashboard/teacher.rb
+++ b/app/services/dashboard/teacher.rb
@@ -2,7 +2,7 @@
 
 class Dashboard::Teacher
   PURCHASE_LIMIT = 30
-  DAYS = %w[Dziś Wczoraj Wcześniej].freeze
+  DAYS = %i[today yesterday earlier].freeze
   RECENT_DAYS = DAYS.first(2).freeze
 
   Purchase = Data.define(:transaction, :student, :story_group, :item, :day) do
@@ -69,7 +69,7 @@ def build_groups
     summaries = story_groups.map do |story_group|
       Group.new(
         story_group:    story_group,
-        role:           story_group.owner_id == @user.id ? 'Prowadzisz' : 'Wspierasz',
+        role:           I18n.t("story_groups.listing.roles.#{story_group.owner_id == @user.id ? 'own' : 'sup'}"),
         students_count: counts.fetch(story_group.id, 0),
         new_purchases:  fresh.fetch(story_group.id, []).size,
       )
diff --git a/app/services/group_chrome.rb b/app/services/group_chrome.rb
index 6995d2bd..17389850 100644
--- a/app/services/group_chrome.rb
+++ b/app/services/group_chrome.rb
@@ -1,13 +1,6 @@
 # frozen_string_literal: true
 
 class GroupChrome
-  ROLE_LABELS = {
-    own: 'Prowadzisz tę grupę',
-    sup: 'Wspierasz tę grupę',
-    lrn: 'Jesteś uczestnikiem',
-    adm: 'Nadzorujesz tę grupę',
-  }.freeze
-
   attr_reader :user, :story_group, :student_membership
 
   class << self
@@ -33,7 +26,9 @@ def member? = student? || owner? || supporting_teacher? || user.administers?(sto
 
   def name = story_group.name
 
-  def role_label = ROLE_LABELS[role]
+  def role_label
+    I18n.t("layouts.chrome_roles.#{role}")
+  end
 
   def role
     return :lrn if student?
diff --git a/app/services/invite_form.rb b/app/services/invite_form.rb
index 82724749..f09d990e 100644
--- a/app/services/invite_form.rb
+++ b/app/services/invite_form.rb
@@ -63,25 +63,25 @@ def save
   def error_for(attribute) = invite.errors[attribute].first
 
   def summary
-    "Kod będzie działał #{limit_phrase} #{expiry_phrase}."
+    text(:sentence, limit: limit_phrase, expiry: expiry_phrase)
   end
 
-  def unit_label = gh_plural(max_uses.to_i, 'osoba', 'osoby', 'osób')
+  def unit_label = text(:unit, count: max_uses.to_i)
 
   private
 
-  def limit_phrase
-    return 'bez limitu osób' unless limit_enabled?
+  def text(key, **) = I18n.t("story_group_invites.summary.#{key}", **)
 
-    count = max_uses.to_i
+  def limit_phrase
+    return text(:no_limit) unless limit_enabled?
 
-    "dla #{count} #{gh_plural(count, 'osoby', 'osób', 'osób')}"
+    text(:limit, count: max_uses.to_i)
   end
 
   def expiry_phrase
-    return 'i bez daty ważności' unless expiry_enabled?
+    return text(:no_expiry) unless expiry_enabled?
 
-    "do #{gh_stamp(combined_expiry)}"
+    text(:expiry, date: gh_stamp(combined_expiry))
   end
 
   def combined_expiry
@@ -92,6 +92,6 @@ def reject_past_expiry
     return unless expiry_enabled?
     return if combined_expiry&.future?
 
-    invite.errors.add(:expires_at, 'Ta data już minęła. Wybierz późniejszą.')
+    invite.errors.add(:expires_at, :past)
   end
 end
diff --git a/app/services/invite_lookup.rb b/app/services/invite_lookup.rb
index 6fe53c2b..4e8a5544 100644
--- a/app/services/invite_lookup.rb
+++ b/app/services/invite_lookup.rb
@@ -1,21 +1,13 @@
 # frozen_string_literal: true
 
 class InviteLookup
-  MESSAGES = {
-    missing:   'Podaj kod zaproszenia.',
-    not_found: 'Nie znaleźliśmy takiego kodu. Sprawdź go z prowadzącym.',
-    expired:   'Ten kod wygasł. Poproś prowadzącego o nowy.',
-    exhausted: 'Z tego kodu skorzystała już maksymalna liczba osób. ' \
-               'Poproś prowadzącego o nowy.',
-  }.freeze
-
   Result = Data.define(:invite, :reason, :member_of) do
     def initialize(invite: nil, reason: nil, member_of: nil)
       super
     end
 
     def ok? = reason.nil? && member_of.nil?
-    def error = reason && MESSAGES[reason]
+    def error = reason && I18n.t("join.errors.#{reason}")
     def story_group = invite&.story_group
   end
 
diff --git a/app/services/item_purchase_service.rb b/app/services/item_purchase_service.rb
index 25ad0d4d..cbcc8342 100644
--- a/app/services/item_purchase_service.rb
+++ b/app/services/item_purchase_service.rb
@@ -28,7 +28,7 @@ def call
       price = PriceCalculatorService.new(price: @item.price, discount: discount_info).calculate
 
       if @student.current_currency < price
-        return Result.new(['Masz za mało waluty, aby kupić ten przedmiot.'])
+        return Result.new([I18n.t('shop.errors.not_enough')])
       end
 
       execute_purchase!(price, discount_info.value)
@@ -38,7 +38,7 @@ def call
 
     Result.new
   rescue StandardError => e
-    Result.new(["Wystąpił błąd podczas zakupu: #{e.message}"])
+    Result.new([I18n.t('shop.errors.failed', message: e.message)])
   end
 
   private
diff --git a/app/services/purchase_eligibility_service.rb b/app/services/purchase_eligibility_service.rb
index 97acb37d..7ea5dcd4 100644
--- a/app/services/purchase_eligibility_service.rb
+++ b/app/services/purchase_eligibility_service.rb
@@ -36,7 +36,7 @@ def call
   def check_lives!
     return unless @student.lives == 0 && !@item.can_buy_at_0_lives
 
-    @errors << 'Wymagane jest posiadanie przynajmniej jednego życia.'
+    @errors << I18n.t('shop.errors.no_lives')
     @reasons << Reason.new(:lives, nil)
   end
 
@@ -45,7 +45,7 @@ def check_rank!
 
     return unless @student.rank.nil? || @student.total_currency < @item.unlock_rank.required_currency_value
 
-    @errors << "Wymagana ranga: #{@item.unlock_rank.name}."
+    @errors << I18n.t('shop.errors.rank_required', rank: @item.unlock_rank.name)
     @reasons << Reason.new(:rank, @item.unlock_rank)
   end
 
@@ -57,7 +57,7 @@ def check_badges!
     return if missing_badges.none?
 
     badge_names = missing_badges.map(&:name).join(', ')
-    @errors << "Brakujące odznaki: #{badge_names}."
+    @errors << I18n.t('shop.errors.badges_missing', badges: badge_names)
     # One reason per badge, unlike the single error above: a card lists them as
     # separate lines and the seal names only the first.
     missing_badges.sort_by { |badge| badge.name.to_s }
diff --git a/app/services/shop.rb b/app/services/shop.rb
index 9943b483..33e8a304 100644
--- a/app/services/shop.rb
+++ b/app/services/shop.rb
@@ -1,11 +1,7 @@
 # frozen_string_literal: true
 
 class Shop
-  ZONES = [
-    [:afford, 'Stać cię teraz'],
-    [:save,   'Zbierasz na to'],
-    [:sealed, 'Zapieczętowane'],
-  ].freeze
+  ZONES = %i[afford save sealed].freeze
 
   KIND_ORDER = { rank: 0, badge: 1, lives: 2 }.freeze
 
@@ -19,10 +15,10 @@ def initialize(story_group:, student:)
   end
 
   def zones
-    @zones ||= ZONES.filter_map do |key, label|
+    @zones ||= ZONES.filter_map do |key|
       found = offers.select { |offer| state_of(offer.item) == key }
 
-      Zone.new(key: key, label: label, offers: found) if found.any?
+      Zone.new(key: key, label: I18n.t("shop.zones.#{key}"), offers: found) if found.any?
     end
   end
 
diff --git a/app/services/starter_pack_builder.rb b/app/services/starter_pack_builder.rb
index 640f44c8..1a7a1415 100644
--- a/app/services/starter_pack_builder.rb
+++ b/app/services/starter_pack_builder.rb
@@ -70,7 +70,7 @@ def create_items(ranks, badges)
   end
 
   def create_template
-    template = story_group.activity_group_templates.new(base_name: StarterPack::TEMPLATE_NAME)
+    template = story_group.activity_group_templates.new(base_name: StarterPack.template_name)
 
     kept(:cats, preset.categories).each_with_index do |category, position|
       template.categories.new(didactic_description: category.didactic_description,
@@ -101,7 +101,7 @@ def row_for(zone, index)
   def guard_threshold!(seen, value, name)
     if seen.key?(value)
       raise InvalidSelection,
-            "Dwie rangi nie mogą mieć tego samego progu: #{seen[value]} i #{name} mają #{value}."
+            I18n.t('story_groups.flash.duplicate_threshold', first: seen[value], second: name, value: value)
     end
 
     seen[value] = name
diff --git a/app/services/story_groups_listing.rb b/app/services/story_groups_listing.rb
index 75331bda..e3ad2021 100644
--- a/app/services/story_groups_listing.rb
+++ b/app/services/story_groups_listing.rb
@@ -1,19 +1,15 @@
 # frozen_string_literal: true
 
 class StoryGroupsListing
-  include ApplicationHelper
-
-  ROLE_LABELS = { own: 'Prowadzisz', sup: 'Wspierasz', lrn: 'Uczysz się' }.freeze
-
   TABS = {
-    nil       => ['Wszystkie', nil],
-    'mine'    => ['Moje',      :own],
-    'teacher' => ['Nauczam',   :sup],
-    'student' => ['Uczę się',  :lrn],
+    nil       => nil,
+    'mine'    => :own,
+    'teacher' => :sup,
+    'student' => :lrn,
   }.freeze
 
   Group = Data.define(:story_group, :role, :students_count, :meta) do
-    def role_label = ROLE_LABELS[role]
+    def role_label = I18n.t("story_groups.listing.roles.#{role}")
   end
 
   Tab = Data.define(:key, :label, :total)
@@ -35,7 +31,7 @@ def load
   private
 
   def matches_filter?(group)
-    role = TABS[filter].last
+    role = TABS[filter]
 
     role.nil? || group.role == role
   end
@@ -71,22 +67,22 @@ def role_for(story_group)
   def meta_for(story_group, role)
     case role
     when :own then owner_meta(story_group)
-    when :sup then "Właściciel: #{story_group.owner.full_name}"
+    when :sup then I18n.t('story_groups.listing.owner', name: story_group.owner.full_name)
     else           student_meta(story_group)
     end
   end
 
   def owner_meta(story_group)
     count = purchase_counts.fetch(story_group.id, 0)
-    return 'Brak nowych zakupów' if count.zero?
+    return I18n.t('story_groups.listing.no_purchases') if count.zero?
 
-    "#{count} #{gh_plural(count, 'nowy zakup', 'nowe zakupy', 'nowych zakupów')}"
+    I18n.t('story_groups.listing.purchases', count: count)
   end
 
   def student_meta(story_group)
     balance = memberships[story_group.id]&.current_currency.to_i
 
-    "Masz #{balance} #{story_group.currency_name}"
+    I18n.t('story_groups.listing.balance', balance: balance, currency: story_group.currency_name)
   end
 
   def teacher_group_ids
@@ -127,11 +123,11 @@ def build_tabs
     total   = all_groups.size
     by_role = all_groups.group_by(&:role)
 
-    TABS.filter_map do |key, (label, role)|
+    TABS.filter_map do |key, role|
       count = role.nil? ? total : by_role.fetch(role, []).size
       next if role && !count.between?(1, total - 1)
 
-      Tab.new(key: key, label: label, total: count)
+      Tab.new(key: key, label: I18n.t("story_groups.listing.tabs.#{key || 'all'}"), total: count)
     end
   end
 end
diff --git a/app/services/student_sheet.rb b/app/services/student_sheet.rb
index a2244115..80604e59 100644
--- a/app/services/student_sheet.rb
+++ b/app/services/student_sheet.rb
@@ -1,17 +1,13 @@
 # frozen_string_literal: true
 
 class StudentSheet
-  TABS = [
-    ['badges', 'Odznaki'],
-    ['items',  'Przedmioty'],
-    ['hist',   'Historia waluty'],
-  ].freeze
+  TABS = %w[badges items hist].freeze
 
   DEFAULT_TAB = 'badges'
 
   class << self
     def tab_for(param)
-      TABS.map(&:first).include?(param.to_s) ? param.to_s : DEFAULT_TAB
+      TABS.include?(param.to_s) ? param.to_s : DEFAULT_TAB
     end
   end
 
diff --git a/app/services/teacher_overview.rb b/app/services/teacher_overview.rb
index 576c3cb4..b39e9305 100644
--- a/app/services/teacher_overview.rb
+++ b/app/services/teacher_overview.rb
@@ -48,13 +48,16 @@ def build_stat_tiles
     earned = window_scope.reward.sum(:amount)
 
     [
-      StatTile.new(label: 'Studenci', value: students_count),
-      StatTile.new(label: 'Zakupy w tym tygodniu', value: bought, note: (spent.positive? ? "za #{spent}" : nil)),
-      StatTile.new(label: 'Nagrody w tym tygodniu', value: earned),
-      StatTile.new(label: 'Ranking', value: story_group.ranking_summary),
+      StatTile.new(label: stat(:students), value: students_count),
+      StatTile.new(label: stat(:purchases), value: bought,
+                   note:  (spent.positive? ? stat(:purchases_note, amount: spent) : nil),),
+      StatTile.new(label: stat(:rewards), value: earned),
+      StatTile.new(label: stat(:ranking), value: story_group.ranking_summary),
     ]
   end
 
+  def stat(key, **) = I18n.t("story_groups.overview.stats.#{key}", **)
+
   def window_scope
     CurrencyTransaction.where(student_id: membership_ids)
                        .where(created_at: WINDOW.ago..)
@@ -83,9 +86,9 @@ def out_of_lives
                .map do |membership|
       AttentionItem.new(
         icon: 'fa-heart', tone: 'zero',
-        title: "#{membership.display_name} ma 0 żyć",
-        detail: 'Kupi tylko przedmioty dostępne przy 0 życiach.',
-        action_label: 'Otwórz',
+        title: I18n.t('story_groups.overview.zero_lives_title', name: membership.display_name),
+        detail: I18n.t('story_groups.overview.zero_lives_detail'),
+        action_label: I18n.t('story_groups.overview.open'),
         action_path: story_group_student_path(story_group, membership),
       )
     end
@@ -104,10 +107,10 @@ def ungraded_sheet
 
     AttentionItem.new(
       icon: 'fa-table', emphasis: true,
-      title: "#{activity_group.name} w trakcie",
-      detail: "Przyznano #{awarded} #{Plural.pick(awarded, 'nagrodę', 'nagrody', 'nagród')}, " \
-              "#{pending} #{Plural.pick(pending, 'kolumna', 'kolumny', 'kolumn')} bez ocen.",
-      action_label: 'Oceń',
+      title: I18n.t('story_groups.overview.sheet_in_progress', name: activity_group.name),
+      detail: "#{I18n.t('story_groups.overview.sheet_awarded', count: awarded)}, " \
+              "#{I18n.t('story_groups.overview.sheet_pending', count: pending)}",
+      action_label: I18n.t('story_groups.overview.grade'),
       action_path: edit_story_group_activity_group_students_activity_group_categories_path(story_group,
                                                                                            activity_group,),
     )
diff --git a/app/values/currency_icons.rb b/app/values/currency_icons.rb
index f8edb3d5..bb2bfb69 100644
--- a/app/values/currency_icons.rb
+++ b/app/values/currency_icons.rb
@@ -3,16 +3,7 @@
 class CurrencyIcons < PresetSet
   KEYS = %w[carrot coin gem pearl bit].freeze
 
-  LABELS = {
-    'bit'    => 'Bit',
-    'carrot' => 'Marchewka',
-    'coin'   => 'Moneta',
-    'gem'    => 'Klejnot',
-    'pearl'  => 'Perła',
-  }.freeze
-
   class << self
     def dir = 'currency'
-    def labels = LABELS
   end
 end
diff --git a/app/values/glyphs.rb b/app/values/glyphs.rb
index f423cf2c..754e51db 100644
--- a/app/values/glyphs.rb
+++ b/app/values/glyphs.rb
@@ -13,36 +13,7 @@ class Glyphs < PresetSet
     shield hourglass chat retake percent paperCheck heartPlus note clock papers3 starPlus flask
   ].freeze
 
-  LABELS = {
-    'bolt'          => 'Błyskawica',
-    'carrot'        => 'Marchewka',
-    'carrotStar'    => 'Marchewka z gwiazdą',
-    'chat'          => 'Rozmowa',
-    'chev1'         => 'Belka',
-    'chev2'         => 'Podwójna belka',
-    'clock'         => 'Zegar',
-    'compass'       => 'Kompas',
-    'crew'          => 'Załoga',
-    'crown'         => 'Korona',
-    'flask'         => 'Kolba',
-    'heartPlus'     => 'Serce z plusem',
-    'hourglass'     => 'Klepsydra',
-    'note'          => 'Koperta',
-    'paperCheck'    => 'Kartka z ptaszkiem',
-    'papers3'       => 'Trzy kartki',
-    'papers3shield' => 'Trzy kartki z tarczą',
-    'percent'       => 'Procent',
-    'rabbit'        => 'Królik',
-    'retake'        => 'Kartka ze strzałką',
-    'rocket'        => 'Rakieta',
-    'shield'        => 'Tarcza',
-    'starPlus'      => 'Gwiazda z gwiazdką',
-    'starTrail'     => 'Gwiazda ze smugą',
-    'wrench'        => 'Klucz',
-  }.freeze
-
   class << self
     def dir = 'glyphs'
-    def labels = LABELS
   end
 end
diff --git a/app/values/group_art.rb b/app/values/group_art.rb
index 47720abc..d7ed6880 100644
--- a/app/values/group_art.rb
+++ b/app/values/group_art.rb
@@ -3,16 +3,7 @@
 class GroupArt < PresetSet
   KEYS = %w[castle waves tables flow brackets].freeze
 
-  LABELS = {
-    'brackets' => 'Kod',
-    'castle'   => 'Zamek',
-    'flow'     => 'Algorytm',
-    'tables'   => 'Tabele',
-    'waves'    => 'Morze',
-  }.freeze
-
   class << self
     def dir = 'art'
-    def labels = LABELS
   end
 end
diff --git a/app/values/item_card.rb b/app/values/item_card.rb
index 9ade76ed..9f9243df 100644
--- a/app/values/item_card.rb
+++ b/app/values/item_card.rb
@@ -69,11 +69,13 @@ def badges_discount = badges.sum { |badge| badge.discount.to_i }
   def discount_label
     return if max_discount.zero?
 
-    "Zniżki do −#{max_discount}%"
+    I18n.t('items.labels.discount_up_to', discount: max_discount)
   end
 
   def lock_labels
-    requirements.map { |requirement| requirement.rank? ? "Od rangi #{requirement.name}" : requirement.name }
+    requirements.map do |requirement|
+      requirement.rank? ? I18n.t('items.labels.lock_rank', name: requirement.name) : requirement.name
+    end
   end
 
   def discounts? = max_discount.positive?
diff --git a/app/values/item_offer.rb b/app/values/item_offer.rb
index 103b7ca8..7a8fec7a 100644
--- a/app/values/item_offer.rb
+++ b/app/values/item_offer.rb
@@ -37,7 +37,7 @@ def discount_label
     return card.discount_label if discount.nil?
     return if discount.value.zero?
 
-    "−#{discount.value}% #{discount_source}"
+    I18n.t('items.labels.discount', discount: discount.value, source: discount_source)
   end
 
   def rank_progress
@@ -53,10 +53,10 @@ def rank_progress
   private
 
   def discount_source
-    return 'za rangę i odznaki' if rank_discount? && badge_discount?
-    return 'za rangę'           if rank_discount?
+    return I18n.t('items.labels.source_rank_and_badges') if rank_discount? && badge_discount?
+    return I18n.t('items.labels.source_rank')            if rank_discount?
 
-    'za odznaki'
+    I18n.t('items.labels.source_badges')
   end
 
   def rank_discount? = student&.rank&.discount.to_i.positive?
diff --git a/app/values/ledger_entry.rb b/app/values/ledger_entry.rb
index 0ab6616f..03f574d2 100644
--- a/app/values/ledger_entry.rb
+++ b/app/values/ledger_entry.rb
@@ -1,12 +1,6 @@
 # frozen_string_literal: true
 
 class LedgerEntry
-  KIND_LABELS = {
-    'reward'     => 'Nagroda',
-    'purchase'   => 'Zakup',
-    'adjustment' => 'Korekta',
-  }.freeze
-
   KIND_TONES = {
     'reward'     => 'earn',
     'purchase'   => 'spend',
@@ -28,7 +22,7 @@ def amount      = transaction.amount.to_i
   def kind        = transaction.kind.to_s
   def occurred_at = transaction.created_at
 
-  def label = KIND_LABELS.fetch(kind, kind)
+  def label = I18n.t("currency_transactions.kinds.#{kind}", default: kind)
   def tone  = KIND_TONES.fetch(kind, 'corr')
 
   def reward?     = kind == 'reward'
diff --git a/app/values/navigation.rb b/app/values/navigation.rb
index 3a8df82a..a48e1633 100644
--- a/app/values/navigation.rb
+++ b/app/values/navigation.rb
@@ -1,10 +1,11 @@
 # frozen_string_literal: true
 
+# Items carry a key so the tab bar can pick them without matching on wording.
 class Navigation
   include Rails.application.routes.url_helpers
 
-  Item = Data.define(:label, :path, :icon, :short, :match, :frame) do
-    def initialize(label:, path:, icon:, short: nil, match: nil, frame: nil)
+  Item = Data.define(:key, :label, :path, :icon, :short, :match, :frame) do
+    def initialize(key:, label:, path:, icon:, short: nil, match: nil, frame: nil)
       super
     end
 
@@ -17,8 +18,8 @@ def current?(current_path)
     end
   end
 
-  TEACHER_TABS = ['Przegląd', 'Studenci', 'Arkusze ocen'].freeze
-  STUDENT_TABS = ['Przegląd', 'Sklep', 'Moje przedmioty', 'Ranking'].freeze
+  TEACHER_TABS = %i[overview students sheets].freeze
+  STUDENT_TABS = %i[overview shop my_items ranking].freeze
 
   def initialize(user)
     @user = user
@@ -26,18 +27,15 @@ def initialize(user)
 
   def primary_items
     [
-      Item.new(label: 'Start',  path: home_path,         icon: 'fa-house'),
-      (Item.new(label: 'Grupy', path: story_groups_path, icon: 'fa-book') unless @user.global_admin?),
+      item(:start,  home_path,         'fa-house'),
+      (item(:groups, story_groups_path, 'fa-book') unless @user.global_admin?),
       organization_item,
     ].compact
   end
 
   def tab_items
     items = primary_items
-    if @user.teacher?
-      items += [Item.new(label: 'Powiadomienia', path: notifications_path,
-                         icon: 'fa-bell', frame: 'panel',)]
-    end
+    items += [item(:notifications, notifications_path, 'fa-bell', frame: 'panel')] if @user.teacher?
 
     items
   end
@@ -50,9 +48,9 @@ def group_items(chrome)
 
   def group_tab_items(chrome)
     wanted = chrome.student? ? STUDENT_TABS : TEACHER_TABS
-    by_label = group_items(chrome).index_by(&:label)
+    by_key = group_items(chrome).index_by(&:key)
 
-    wanted.filter_map { |label| by_label[label] }
+    wanted.filter_map { |key| by_key[key] }
   end
 
   private
@@ -62,14 +60,14 @@ def teacher_items(chrome)
 
     [
       overview(group),
-      section('Studenci',     story_group_students_path(group),         'fa-graduation-cap'),
-      section('Arkusze ocen', story_group_activity_groups_path(group),  'fa-table', short: 'Arkusze'),
-      section('Przedmioty',   story_group_items_path(group),            'fa-flask'),
+      section(:students, story_group_students_path(group),        'fa-graduation-cap'),
+      section(:sheets,   story_group_activity_groups_path(group), 'fa-table', short: true),
+      section(:items,    story_group_items_path(group),           'fa-flask'),
       *shared_items(group),
       ranking_item(chrome),
-      section('Zaproszenia',  story_group_invites_path(group),          'fa-qrcode'),
-      section('Nauczyciele',  story_group_teachers_path(group),         'fa-briefcase'),
-      section('Ustawienia grupy', edit_story_group_path(group),         'fa-gear'),
+      section(:invites,  story_group_invites_path(group),         'fa-qrcode'),
+      section(:teachers, story_group_teachers_path(group),        'fa-briefcase'),
+      section(:settings, edit_story_group_path(group),            'fa-gear'),
     ]
   end
 
@@ -79,47 +77,54 @@ def student_items(chrome)
 
     [
       overview(group),
-      section('Sklep', story_group_shop_index_path(group), 'fa-sack-dollar'),
-      section('Moje przedmioty',
+      section(:shop, story_group_shop_index_path(group), 'fa-sack-dollar'),
+      section(:my_items,
               story_group_student_students_items_path(group, membership),
-              'fa-flask', short: 'Przedmioty',),
+              'fa-flask', short: true,),
       *shared_items(group),
-      section('Historia waluty',
+      section(:history,
               story_group_student_currency_transactions_path(group, membership),
               'fa-clock-rotate-left',),
       ranking_item(chrome),
-      section('Ustawienia w grupie', edit_story_group_membership_path(group), 'fa-gear'),
+      section(:membership, edit_story_group_membership_path(group), 'fa-gear'),
     ]
   end
 
   def shared_items(group)
     [
-      section('Rangi',   story_group_ranks_path(group),  'fa-angles-up'),
-      section('Odznaki', story_group_badges_path(group), 'fa-award'),
+      section(:ranks,  story_group_ranks_path(group),  'fa-angles-up'),
+      section(:badges, story_group_badges_path(group), 'fa-award'),
     ]
   end
 
   def ranking_item(chrome)
     return unless chrome.ranking?
 
-    section('Ranking', story_group_ranking_path(chrome.story_group), 'fa-ranking-star')
+    section(:ranking, story_group_ranking_path(chrome.story_group), 'fa-ranking-star')
   end
 
   def organization_item
     if @user.global_admin?
-      Item.new(label: 'Organizacje', path: organizations_path, icon: 'fa-briefcase', match: organizations_path)
+      section(:organizations, organizations_path, 'fa-briefcase')
     elsif @user.organization_admin? && @user.organization
       path = organization_path(@user.organization)
-      Item.new(label: @user.organization.name, path: path, icon: 'fa-briefcase',
-               short: 'Organizacja', match: path,)
+      Item.new(key: :organization, label: @user.organization.name, path: path, icon: 'fa-briefcase',
+               short: label('short.organization'), match: path,)
     end
   end
 
   def overview(group)
-    Item.new(label: 'Przegląd', path: story_group_path(group), icon: 'fa-table-columns')
+    item(:overview, story_group_path(group), 'fa-table-columns')
+  end
+
+  def item(key, path, icon, frame: nil)
+    Item.new(key: key, label: label(key), path: path, icon: icon, frame: frame)
   end
 
-  def section(label, path, icon, short: nil)
-    Item.new(label: label, path: path, icon: icon, short: short, match: path)
+  def section(key, path, icon, short: false)
+    Item.new(key: key, label: label(key), path: path, icon: icon, match: path,
+             short: (label("short.#{key}") if short),)
   end
+
+  def label(key) = I18n.t("layouts.navigation.#{key}")
 end
diff --git a/app/values/plural.rb b/app/values/plural.rb
deleted file mode 100644
index fe83e65f..00000000
--- a/app/values/plural.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-# frozen_string_literal: true
-
-module Plural
-  extend self
-
-  def pick(count, one, few, many)
-    n        = count.abs
-    last_two = n % 100
-    last_one = n % 10
-
-    return one if n == 1
-    return few if last_one.between?(2, 4) && !last_two.between?(12, 14)
-
-    many
-  end
-end
diff --git a/app/values/preset_set.rb b/app/values/preset_set.rb
index 2fdddcb7..34032169 100644
--- a/app/values/preset_set.rb
+++ b/app/values/preset_set.rb
@@ -3,10 +3,9 @@
 class PresetSet
   class << self
     def dir = raise(NotImplementedError, "#{name} must define .dir")
-    def labels = {}.freeze
 
     def label_for(key)
-      labels.fetch(key.to_s, key.to_s)
+      I18n.t("application.presets.#{dir}.#{key}", default: key.to_s)
     end
 
     def all
diff --git a/app/values/requirement_phrasing.rb b/app/values/requirement_phrasing.rb
index 1a74b783..746e2971 100644
--- a/app/values/requirement_phrasing.rb
+++ b/app/values/requirement_phrasing.rb
@@ -11,17 +11,19 @@ def lives? = kind == :lives
 
   def seal_label_for(requirement)
     return if requirement.nil?
-    return 'Niedostępne przy 0 życiach' if requirement.lives?
+    return I18n.t('items.labels.seal_lives') if requirement.lives?
 
-    requirement.rank? ? "Od rangi #{requirement.name}" : "Za odznakę #{requirement.name}"
+    key = requirement.rank? ? 'items.labels.seal_rank' : 'items.labels.seal_badge'
+    I18n.t(key, name: requirement.name)
   end
 
+  # [lead, name] pairs; the view sets the name in bold after the lead.
   def requirement_lines_for(requirements)
     requirements.map do |requirement|
       case requirement.kind
-      when :rank  then ['Wymaga rangi ',   requirement.name]
-      when :badge then ['Wymaga odznaki ', requirement.name]
-      else             ['Masz 0 żyć. Najpierw odzyskaj życie.', nil]
+      when :rank  then [I18n.t('items.labels.requires_rank'),  requirement.name]
+      when :badge then [I18n.t('items.labels.requires_badge'), requirement.name]
+      else             [I18n.t('items.labels.requires_life'),  nil]
       end
     end
   end
diff --git a/app/values/starter_pack.rb b/app/values/starter_pack.rb
index a49f67f2..bf55682e 100644
--- a/app/values/starter_pack.rb
+++ b/app/values/starter_pack.rb
@@ -1,6 +1,12 @@
 # frozen_string_literal: true
 
+# The quick-start set. Numbers and icons live here; every name and description
+# comes from story_groups.starter_pack in config/locales/views/story_groups.*.yml,
+# in the language of whoever creates the group — the builder writes them to the
+# database as plain text, so a group keeps the language it was created in.
 class StarterPack
+  I18N_SCOPE = 'story_groups.starter_pack'
+
   CLASS_MAX = 11
 
   KEYS = %w[neutral fantasy scifi].freeze
@@ -8,20 +14,6 @@ class StarterPack
   CLASSES_RANGE   = (4..30)
   DEFAULT_CLASSES = 12
 
-  LABELS = {
-    'neutral' => 'Neutralny',
-    'fantasy' => 'Fantasy',
-    'scifi'   => 'Sci-fi',
-  }.freeze
-
-  DESCRIPTIONS = {
-    'neutral' => 'Bez fabularnego klimatu. Pasuje do każdego przedmiotu.',
-    'fantasy' => 'Zamki, zakony i rycerskie tytuły.',
-    'scifi'   => 'Statki, załogi i kosmiczne misje.',
-  }.freeze
-
-  TEMPLATE_NAME = 'Zajęcia'
-
   Rank     = Data.define(:index, :name, :threshold, :discount, :icon_glyph)
   Badge    = Data.define(:index, :name, :didactic_description, :story_description, :discount,
                          :icon_glyph,)
@@ -29,202 +21,60 @@ class StarterPack
                          :unlock_rank, :min_rank_for_discount, :discount_badges, :can_buy_at_0_lives,)
   Category = Data.define(:index, :didactic_description, :story_description, :reward)
 
-  CATEGORIES = [
-    ['Obecność',                   1],
-    ['Punktualność',               1],
-    ['Wejściówka zaliczona',       1],
-    ['Wejściówka ≥ średnia grupy', 2],
-    ['Zgłoszenie do zadania',      2],
-    ['Zadanie zrobione poprawnie', 1],
-    ['Pomoc innym',                2],
-    ['Ciekawa uwaga',              1],
-  ].freeze
+  # Reward per category, in the order of starter_pack.categories.
+  CATEGORY_REWARDS = [1, 1, 1, 2, 2, 1, 2, 1].freeze
 
   RANK_FRACTIONS = [0.0, 0.15, 0.30, 0.50, 0.75].freeze
   RANK_DISCOUNTS = [0, 3, 5, 10, 15].freeze
 
-  BADGE_RULES = [
-    'Pierwsza wejściówka bez błędów',
-    'Obecność na wszystkich zajęciach w miesiącu',
-    'Co najmniej 3 razy pomógł innym',
-    'Co najmniej 3 ciekawe uwagi',
-    '3 wejściówki z rzędu ≥ średniej grupy',
-    'Wyjaśnienie trudnego zadania całej grupie',
-  ].freeze
-
   BADGE_DISCOUNTS = [2, 5, 5, 3, 5, 7].freeze
 
+  # In the order of starter_pack.items.
   ITEMS = [
-    {
-      name:            '+5 minut do wejściówki',
-      x:               1.0,
-      glyph:           'clock',
-      unlock:          nil,
-      discount_rank:   2,
-      discount_badges: [],
-      didactic:        'Dodaje 5 minut do czasu na najbliższą wejściówkę.',
-    },
-    {
-      name:            'Konsultacja',
-      x:               1.5,
-      glyph:           'chat',
-      unlock:          nil,
-      discount_rank:   2,
-      discount_badges: [],
-      didactic:        'Kwadrans konsultacji z prowadzącym poza zajęciami.',
-    },
-    {
-      name:            'Poprawa wejściówki',
-      x:               1.0,
-      glyph:           'retake',
-      unlock:          1,
-      discount_rank:   3,
-      discount_badges: [],
-      didactic:        'Pozwala napisać jedną wejściówkę jeszcze raz.',
-    },
-    {
-      name:            'Bezpieczna poprawa',
-      x:               2.0,
-      glyph:           'shield',
-      unlock:          2,
-      discount_rank:   3,
-      discount_badges: [1, 3],
-      didactic:        'Poprawa wejściówki bez ryzyka — liczy się lepszy z dwóch wyników.',
-    },
-    {
-      name:            'Usprawiedliwienie',
-      x:               2.5,
-      glyph:           'note',
-      unlock:          2,
-      discount_rank:   3,
-      discount_badges: [],
-      didactic:        'Usprawiedliwia jedną nieobecność, bez utraty życia.',
-    },
-    {
-      name:            '1up: odzyskanie życia',
-      m:               0.25,
-      glyph:           'heartPlus',
-      unlock:          nil,
-      discount_rank:   4,
-      discount_badges: [3, 5, 2],
-      at_zero_lives:   true,
-      didactic:        'Przywraca jedno utracone życie.',
-    },
-    {
-      name:            '+0.5 oceny końcowej',
-      m:               0.60,
-      glyph:           'percent',
-      unlock:          3,
-      discount_rank:   4,
-      discount_badges: [5, 1],
-      didactic:        'Podnosi ocenę końcową o pół stopnia.',
-    },
+    { x: 1.0,  glyph: 'clock',     unlock: nil, discount_rank: 2, discount_badges: [] },
+    { x: 1.5,  glyph: 'chat',      unlock: nil, discount_rank: 2, discount_badges: [] },
+    { x: 1.0,  glyph: 'retake',    unlock: 1,   discount_rank: 3, discount_badges: [] },
+    { x: 2.0,  glyph: 'shield',    unlock: 2,   discount_rank: 3, discount_badges: [1, 3] },
+    { x: 2.5,  glyph: 'note',      unlock: 2,   discount_rank: 3, discount_badges: [] },
+    { m: 0.25, glyph: 'heartPlus', unlock: nil, discount_rank: 4, discount_badges: [3, 5, 2], at_zero_lives: true },
+    { m: 0.60, glyph: 'percent',   unlock: 3,   discount_rank: 4, discount_badges: [5, 1] },
   ].freeze
 
-  RANK_NAMES = {
-    'neutral' => %w[Nowicjusz Uczeń Adept Ekspert Mistrz],
-    'fantasy' => %w[Giermek Rycerz Kasztelan Hetman Król],
-    'scifi'   => %w[Kadet Pilot Nawigator Komandor Admirał],
-  }.freeze
-
   RANK_GLYPHS = {
     'neutral' => %w[chev1 chev2 shield starPlus crown],
     'fantasy' => %w[chev1 chev2 shield crown carrotStar],
     'scifi'   => %w[chev1 chev2 rocket compass crown],
   }.freeze
 
-  BADGE_NAMES = {
-    'neutral' => ['Bez skazy',
-                  'Stała obecność',
-                  'Pomocna dłoń',
-                  'Iskra ciekawości',
-                  'Seria sukcesów',
-                  'Głos grupy',],
-    'fantasy' => ['Czysta klinga',
-                  'Wierna straż',
-                  'Tarcza drużyny',
-                  'Księga mądrości',
-                  'Pasmo zwycięstw',
-                  'Bard drużyny',],
-    'scifi'   => ['Czysty lot',
-                  'Zawsze na pokładzie',
-                  'Mechanik załogi',
-                  'Sygnał z kosmosu',
-                  'Seria misji',
-                  'Głos floty',],
-  }.freeze
-
   BADGE_GLYPHS = {
     'neutral' => %w[starPlus shield heartPlus bolt starTrail crew],
     'fantasy' => %w[starPlus shield heartPlus bolt starTrail crown],
     'scifi'   => %w[starPlus rocket wrench compass starTrail crew],
   }.freeze
 
-  BADGE_STORIES = {
-    'neutral' => [nil] * 6,
-    'fantasy' => ['Stal bez jednej rysy — pierwszy pojedynek wygrany bez draśnięcia.',
-                  'Stałeś na posterunku każdej nocy tego miesiąca.',
-                  'Trzykrotnie zasłoniłeś towarzysza własną tarczą.',
-                  'Trzy razy dopisałeś coś, czego w księgach jeszcze nie było.',
-                  'Trzy potyczki z rzędu rozstrzygnięte na twoją korzyść.',
-                  'Wytłumaczyłeś całej drużynie to, czego nikt inny nie potrafił nazwać.',],
-    'scifi'   => ['Pierwszy lot bez jednego odczytu w czerwieni.',
-                  'Ani jednej zmiany opuszczonej w tym cyklu.',
-                  'Trzy razy postawiłeś na nogi cudzy sprzęt.',
-                  'Trzy razy wychwyciłeś sygnał, który inni przegapili.',
-                  'Trzy misje z rzędu zaliczone powyżej normy floty.',
-                  'Twoje wyjaśnienie poszło na cały kanał i wszyscy zrozumieli.',],
-  }.freeze
+  class << self
+    def include?(key) = KEYS.include?(key.to_s)
 
-  ITEM_STORIES = {
-    'neutral' => [nil] * 7,
-    'fantasy' => ['Klepsydra sypie piaskiem wolniej, niż powinna.',
-                  'Audiencja u mistrza zakonu.',
-                  'Drugie podejście do pojedynku.',
-                  'Pojedynek na tępe klingi — przegrana nic nie kosztuje.',
-                  'List żelazny tłumaczący twoją nieobecność.',
-                  'Eliksir przywracający życie.',
-                  'Pieczęć króla na twoim świadectwie.',],
-    'scifi'   => ['Chwilowe spowolnienie zegara pokładowego.',
-                  'Połączenie z komandorem poza godzinami służby.',
-                  'Drugie podejście do symulacji.',
-                  'Lot treningowy — awaria nic nie kosztuje.',
-                  'Wpis do dziennika usprawiedliwiający nieobecność.',
-                  'Regeneracja w kapsule medycznej.',
-                  'Awans wpisany do akt floty.',],
-  }.freeze
+    def label_for(key) = text("packs.#{key}.label", default: key.to_s)
 
-  CATEGORY_STORIES = {
-    'neutral' => [nil] * 8,
-    'fantasy' => ['Stawiłeś się na zbiórce.',
-                  'Na miejscu, zanim zabrzmiał róg.',
-                  'Próba sprawności zaliczona.',
-                  'Wynik powyżej średniej drużyny.',
-                  'Zgłosiłeś się na ochotnika.',
-                  'Zadanie wykonane bez zarzutu.',
-                  'Podałeś rękę towarzyszowi.',
-                  'Rzuciłeś światło na rzecz, której nikt nie dostrzegł.',],
-    'scifi'   => ['Zameldowałeś się na pokładzie.',
-                  'Na stanowisku przed odliczaniem.',
-                  'Test kwalifikacyjny zaliczony.',
-                  'Wynik powyżej średniej załogi.',
-                  'Zgłosiłeś się do zadania.',
-                  'Zadanie wykonane zgodnie z procedurą.',
-                  'Wsparłeś innego członka załogi.',
-                  'Zauważyłeś coś, co umknęło czujnikom.',],
-  }.freeze
+    def description_for(key) = text("packs.#{key}.description", default: '')
 
-  class << self
-    def include?(key) = KEYS.include?(key.to_s)
+    def rank_names(key) = list("packs.#{key}.ranks")
 
-    def label_for(key) = LABELS.fetch(key.to_s, key.to_s)
+    def template_name = text('template_name')
 
-    def description_for(key) = DESCRIPTIONS.fetch(key.to_s, '')
+    def category_names = text('categories')
 
     def for(pack:, classes:)
       new(pack:    include?(pack) ? pack.to_s : KEYS.first,
           classes: classes.to_i.clamp(CLASSES_RANGE.min, CLASSES_RANGE.max),)
     end
+
+    def text(key, **) = I18n.t("#{I18N_SCOPE}.#{key}", **)
+
+    # An array key, or [] when absent. Not `default: []` — I18n reads an Array
+    # default as fallback keys, and an empty list of them is still missing.
+    def list(key) = I18n.exists?("#{I18N_SCOPE}.#{key}") ? text(key) : []
   end
 
   def initialize(pack:, classes:)
@@ -241,7 +91,7 @@ def total_earnable = classes * CLASS_MAX
 
   def ranks
     @ranks ||= begin
-      names  = RANK_NAMES[pack]
+      names  = self.class.rank_names(pack)
       glyphs = RANK_GLYPHS[pack]
 
       thresholds = RANK_FRACTIONS.each_with_object([]) do |fraction, kept|
@@ -258,13 +108,14 @@ def ranks
 
   def badges
     @badges ||= begin
-      names   = BADGE_NAMES[pack]
+      names   = pack_text(:badges)
+      rules   = self.class.text('badge_rules')
       glyphs  = BADGE_GLYPHS[pack]
-      stories = BADGE_STORIES[pack]
+      stories = pack_text(:badge_stories)
 
       names.each_with_index.map do |name, index|
         Badge.new(index: index, name: name,
-                  didactic_description: BADGE_RULES[index],
+                  didactic_description: rules[index],
                   story_description: stories[index],
                   discount: BADGE_DISCOUNTS[index], icon_glyph: glyphs[index],)
       end
@@ -273,11 +124,12 @@ def badges
 
   def items
     @items ||= begin
-      stories = ITEM_STORIES[pack]
+      texts   = self.class.text('items')
+      stories = pack_text(:item_stories)
 
       ITEMS.each_with_index.map do |spec, index|
-        Item.new(index: index, name: spec[:name], price: price_for(spec),
-                 didactic_description: spec[:didactic],
+        Item.new(index: index, name: texts[index][:name], price: price_for(spec),
+                 didactic_description: texts[index][:didactic],
                  story_description: stories[index],
                  icon_glyph: spec[:glyph],
                  unlock_rank: spec[:unlock],
@@ -290,17 +142,20 @@ def items
 
   def categories
     @categories ||= begin
-      stories = CATEGORY_STORIES[pack]
+      stories = pack_text(:category_stories)
 
-      CATEGORIES.each_with_index.map do |(label, reward), index|
+      self.class.category_names.each_with_index.map do |label, index|
         Category.new(index: index, didactic_description: label,
-                     story_description: stories[index], reward: reward,)
+                     story_description: stories[index], reward: CATEGORY_REWARDS[index],)
       end
     end
   end
 
   private
 
+  # A pack without story lines (neutral) simply has no such key.
+  def pack_text(key) = self.class.list("packs.#{pack}.#{key}")
+
   def price_for(spec)
     raw = spec[:x] ? spec[:x] * CLASS_MAX : spec[:m] * total_earnable
 
diff --git a/app/views/account_setups/edit.html.haml b/app/views/account_setups/edit.html.haml
index b2913c78..2525ebad 100644
--- a/app/views/account_setups/edit.html.haml
+++ b/app/views/account_setups/edit.html.haml
@@ -1,20 +1,20 @@
-- content_for :title, 'Konfiguracja konta'
+- content_for :title, t('.page_title')
 
-%h1.gh-h1 Uzupełnij swoje dane
-%p.gh-lead To jednorazowy krok. Imię i nazwisko zobaczą prowadzący w Twoich grupach.
+%h1.gh-h1= t('.title')
+%p.gh-lead= t('.lead')
 
 = form_with model: @current_user, url: account_setup_path, method: :patch do |f|
   .gh-form-field
-    = f.label :email, 'Adres e-mail'
+    = f.label :email, t('.email')
     .gh-text-input
       = f.email_field :email, disabled: true
 
   = render 'organizations/field', form: f, record: @current_user, attribute: :full_name,
-                                  label: 'Imię i nazwisko',
+                                  label: t('.full_name'),
                                   options: { maxlength: 80, autofocus: true, required: true,
-                                             autocomplete: 'name', placeholder: 'Jan Nowak' }
+                                             autocomplete: 'name', placeholder: t('.full_name_placeholder') }
 
   .gh-button-stack
-    %button.gh-btn{ type: 'submit' } Zapisz i przejdź dalej
+    %button.gh-btn{ type: 'submit' }= t('.submit')
 
-= button_to 'Wyloguj', logout_path, method: :delete, class: 'gh-link-button'
+= button_to t('.logout'), logout_path, method: :delete, class: 'gh-link-button'
diff --git a/app/views/activity_group_templates/_confirm_destroy.html.haml b/app/views/activity_group_templates/_confirm_destroy.html.haml
index 2c6ea4e9..b4b7040c 100644
--- a/app/views/activity_group_templates/_confirm_destroy.html.haml
+++ b/app/views/activity_group_templates/_confirm_destroy.html.haml
@@ -1,22 +1,19 @@
-%h2#gh-del-title.gh-h2= "Usunąć szablon „#{template.base_name}”?"
-%p Szablon zniknie z listy, a utworzone z niego arkusze zostają.
+%h2#gh-del-title.gh-h2= t('.title', name: template.base_name)
+%p= t('.body')
 
 - if sheet_names.any?
   %p.gh-info-banner
     %i.fa-solid.fa-table{ 'aria-hidden': 'true' }
-    %span
-      = "#{sheet_names.size} #{gh_plural(sheet_names.size, 'arkusz', 'arkusze', 'arkuszy')}"
-      = "#{gh_plural(sheet_names.size, 'zostaje', 'zostają', 'zostaje')} bez zmian:"
-      = gh_and_list(sheet_names)
+    %span= t('.sheets', count: sheet_names.size, names: gh_and_list(sheet_names))
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', edit_story_group_activity_group_template_path(@story_group, template),
+    = link_to t('shared.actions.cancel'), edit_story_group_activity_group_template_path(@story_group, template),
       class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń szablon', story_group_activity_group_template_path(@story_group, template),
+  = button_to t('.remove'), story_group_activity_group_template_path(@story_group, template),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/activity_group_templates/confirm_destroy.html.haml b/app/views/activity_group_templates/confirm_destroy.html.haml
index f278387b..03318dde 100644
--- a/app/views/activity_group_templates/confirm_destroy.html.haml
+++ b/app/views/activity_group_templates/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń szablon #{@activity_group_template.base_name}"
+- content_for :title, t('.page_title', name: @activity_group_template.base_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/activity_group_templates/edit.html.haml b/app/views/activity_group_templates/edit.html.haml
index 7c45851d..5a3fcb1c 100644
--- a/app/views/activity_group_templates/edit.html.haml
+++ b/app/views/activity_group_templates/edit.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Edytuj szablon #{@activity_group_template.base_name}"
+- content_for :title, t('.page_title', name: @activity_group_template.base_name)
 
 = render 'shared/sheet_form', record: @activity_group_template, variant: :template_edit,
   sheet_names: @sheet_names
diff --git a/app/views/activity_group_templates/new.html.haml b/app/views/activity_group_templates/new.html.haml
index 9830432a..c0b82cbc 100644
--- a/app/views/activity_group_templates/new.html.haml
+++ b/app/views/activity_group_templates/new.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, 'Nowy szablon arkusza'
+- content_for :title, t('.page_title')
 
 = render 'shared/sheet_form', record: @activity_group_template, variant: :template_new
diff --git a/app/views/activity_groups/_confirm_destroy.html.haml b/app/views/activity_groups/_confirm_destroy.html.haml
index d43c2d11..4ea17021 100644
--- a/app/views/activity_groups/_confirm_destroy.html.haml
+++ b/app/views/activity_groups/_confirm_destroy.html.haml
@@ -1,21 +1,21 @@
-%h2#gh-del-title.gh-h2= "Usunąć arkusz „#{activity_group.name}”?"
-%p Arkusz zniknie z listy, a przyznane nagrody zostają u studentów i w ich historii.
+%h2#gh-del-title.gh-h2= t('.title', name: activity_group.name)
+%p= t('.body')
 
 - if awards_count.positive?
   %p.gh-info-banner
     %i.fa-solid.fa-lock{ 'aria-hidden': 'true' }
     %span
-      = "Przyznano z niego #{awards_count} #{gh_plural(awards_count, 'nagrodę', 'nagrody', 'nagród')}."
-      Usunięcie arkusza niczego nie cofa.
+      = t('.awarded', count: awards_count)
+      = t('.nothing_undone')
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', edit_story_group_activity_group_path(@story_group, activity_group),
+    = link_to t('shared.actions.cancel'), edit_story_group_activity_group_path(@story_group, activity_group),
       class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń arkusz', story_group_activity_group_path(@story_group, activity_group),
+  = button_to t('.remove'), story_group_activity_group_path(@story_group, activity_group),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/activity_groups/_new_form.html.haml b/app/views/activity_groups/_new_form.html.haml
index 6d542d25..74f8a699 100644
--- a/app/views/activity_groups/_new_form.html.haml
+++ b/app/views/activity_groups/_new_form.html.haml
@@ -1,53 +1,53 @@
 - count   = ActivityGroupsController::BULK_RANGE.min + 1
 - columns = template.categories.size
 
-%h2#gh-new-sheet-title.gh-h2= "Nowy arkusz z szablonu #{template.base_name}"
+%h2#gh-new-sheet-title.gh-h2= t('.title', name: template.base_name)
 %p
-  = "Każdy arkusz dostanie #{columns} #{gh_plural(columns, 'kategorię', 'kategorie', 'kategorii')} z szablonu."
-  Kolumny zmienisz później w ustawieniach arkusza.
+  = t('.columns', count: columns)
+  = t('.columns_note')
 
 - form_data = { controller: 'sheet-create',
-                sheet_create_sheets_value: %w[arkusz arkusze arkuszy].to_json,
+                sheet_create_i18n_value: t('.js').to_json,
                 turbo_frame: (@in_modal ? 'modal' : nil) }
 
 = form_with url: story_group_activity_groups_path(@story_group), method: :post, data: form_data do |f|
   = hidden_field_tag 'activity_group[activity_group_template_id]', template.id
 
-  .gh-segmented-toggle-3.gh-octagon-clip{ role: 'radiogroup', 'aria-label': 'Ile arkuszy' }
-    - [%w[one Jeden\ arkusz], %w[many Kilka\ naraz]].each do |value, label|
+  .gh-segmented-toggle-3.gh-octagon-clip{ role: 'radiogroup', 'aria-label': t('.how_many') }
+    - [['one', t('.one')], ['many', t('.many')]].each do |value, label|
       %label.gh-segmented-toggle-3-option
         = radio_button_tag 'activity_group[mode]', value, value == 'one',
           data: { sheet_create_target: 'mode', action: 'sheet-create#refresh' }
         %span= label
 
   .gh-form-field{ data: { sheet_create_target: 'onePane' } }
-    = label_tag 'gh-sheet-name', 'Nazwa'
+    = label_tag 'gh-sheet-name', t('shared.actions.name')
     .gh-text-input
       = text_field_tag 'activity_group[name]', suggested_names.first, id: 'gh-sheet-name',
         autocomplete: 'off', autofocus: true
-    %span.gh-field-hint= "Możesz dopisać datę, np. #{suggested_names.first} (14.10)."
+    %span.gh-field-hint= t('.name_hint', example: suggested_names.first)
 
   .gh-form-field{ data: { sheet_create_target: 'manyPane' } }
-    %p#gh-sheet-count-label.gh-form-label Ile arkuszy utworzyć
+    %p#gh-sheet-count-label.gh-form-label= t('.count')
     .gh-number-stepper{ role: 'group', 'aria-labelledby': 'gh-sheet-count-label' }
-      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Mniej',
+      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('shared.actions.fewer'),
                           data: { sheet_create_target: 'down', action: 'sheet-create#down' } }
         %i.fa-solid.fa-minus{ 'aria-hidden': 'true' }
       %output{ 'aria-live': 'polite', data: { sheet_create_target: 'output' } }= count
-      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Więcej',
+      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('shared.actions.more'),
                           data: { sheet_create_target: 'up', action: 'sheet-create#up' } }
         %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
     = hidden_field_tag :count, count, data: { sheet_create_target: 'count' }
 
-    .gh-sample-name-chips{ 'aria-label': 'Nazwy' }
+    .gh-sample-name-chips{ 'aria-label': t('.names') }
       - suggested_names.each_with_index do |name, index|
         %span.gh-octagon-clip{ hidden: index >= count, data: { sheet_create_target: 'name' } }= name
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
     - else
-      = link_to 'Anuluj', story_group_activity_groups_path(@story_group), class: 'gh-btn gh-btn--secondary'
+      = link_to t('shared.actions.cancel'), story_group_activity_groups_path(@story_group), class: 'gh-btn gh-btn--secondary'
     %button.gh-btn{ type: 'submit', data: { sheet_create_target: 'submit' } }
       %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      %span{ data: { sheet_create_target: 'submitLabel' } } Utwórz arkusz
+      %span{ data: { sheet_create_target: 'submitLabel' } }= t('.js.create_one')
diff --git a/app/views/activity_groups/_sheet_row.html.haml b/app/views/activity_groups/_sheet_row.html.haml
index a3d504a3..6d0aae57 100644
--- a/app/views/activity_groups/_sheet_row.html.haml
+++ b/app/views/activity_groups/_sheet_row.html.haml
@@ -4,18 +4,18 @@
   %span.gh-sheet-row-name
     %b= record.name
     - if sheet.columns_modified?
-      %span.gh-tag.gh-tag--modified Zmienione kolumny
+      %span.gh-tag.gh-tag--modified= t('.modified')
 
   %span.gh-sheet-row-stats
     - if sheet.graded?
-      = "Przyznano #{sheet.awards_count} #{gh_plural(sheet.awards_count, 'nagrodę', 'nagrody', 'nagród')}"
+      = t('.awarded', count: sheet.awards_count)
     - else
-      Jeszcze nic nie przyznano
+      = t('.nothing')
 
   %span.gh-sheet-row-actions
-    = link_to 'Oceń',
+    = link_to t('.grade'),
       edit_story_group_activity_group_students_activity_group_categories_path(@story_group, record),
       class: "gh-btn gh-btn--small#{' gh-btn--secondary' unless primary}"
     = link_to edit_story_group_activity_group_path(@story_group, record),
-      class: 'gh-icon-button', title: 'Ustawienia arkusza', 'aria-label': "Ustawienia: #{record.name}" do
+      class: 'gh-icon-button', title: t('.settings'), 'aria-label': t('.settings_label', name: record.name) do
       %i.fa-solid.fa-gear{ 'aria-hidden': 'true' }
diff --git a/app/views/activity_groups/_template_panel.html.haml b/app/views/activity_groups/_template_panel.html.haml
index b4b628ae..467e490b 100644
--- a/app/views/activity_groups/_template_panel.html.haml
+++ b/app/views/activity_groups/_template_panel.html.haml
@@ -1,21 +1,19 @@
 - record = template.record
-- count  = template.category_count
 
 %section.gh-panel.gh-template-panel{ 'aria-labelledby': "gh-tpl-#{record.id}" }
   .gh-template-panel-header
     %div
       %h2.gh-h2{ id: "gh-tpl-#{record.id}" }= record.base_name
       %p.gh-template-panel-meta
-        = "Szablon: #{count} #{gh_plural(count, 'kategoria', 'kategorie', 'kategorii')},"
-        = "do #{template.max_reward} #{@story_group.currency_name} na studenta za arkusz."
+        = t('.meta', count: template.category_count, max: template.max_reward, currency: @story_group.currency_name)
     %span.gh-template-panel-spacer
 
-    = link_to 'Edytuj szablon', edit_story_group_activity_group_template_path(@story_group, record),
+    = link_to t('.edit'), edit_story_group_activity_group_template_path(@story_group, record),
       class: 'gh-btn gh-btn--secondary gh-btn--small'
     = link_to new_story_group_activity_group_path(@story_group, template_id: record.id),
       class: 'gh-btn gh-btn--small', data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      Utwórz arkusz
+      = t('.create_sheet')
 
   - if template.any_sheets?
     %ul.gh-sheet-list
@@ -23,4 +21,4 @@
         = render 'sheet_row', sheet: sheet, primary: index.zero?,
           fresh: fresh_sheet_ids.include?(sheet.record.id)
   - else
-    %p.gh-explainer-note Z tego szablonu nie utworzono jeszcze arkuszy.
+    %p.gh-explainer-note= t('.no_sheets')
diff --git a/app/views/activity_groups/confirm_destroy.html.haml b/app/views/activity_groups/confirm_destroy.html.haml
index 59275650..90461e93 100644
--- a/app/views/activity_groups/confirm_destroy.html.haml
+++ b/app/views/activity_groups/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń arkusz #{@activity_group.name}"
+- content_for :title, t('.page_title', name: @activity_group.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/activity_groups/edit.html.haml b/app/views/activity_groups/edit.html.haml
index 8f984ab0..dd5877a0 100644
--- a/app/views/activity_groups/edit.html.haml
+++ b/app/views/activity_groups/edit.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Ustawienia arkusza #{@activity_group.name}"
+- content_for :title, t('.page_title', name: @activity_group.name)
 
 = render 'shared/sheet_form', record: @activity_group, variant: :sheet,
   awards_count: @activity_group.activity_group_categories.sum(&:awards_count)
diff --git a/app/views/activity_groups/index.html.haml b/app/views/activity_groups/index.html.haml
index 253543ee..653fc315 100644
--- a/app/views/activity_groups/index.html.haml
+++ b/app/views/activity_groups/index.html.haml
@@ -1,21 +1,19 @@
-- content_for :title, 'Arkusze ocen'
+- content_for :title, t('.title')
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Arkusze ocen
-    %p.gh-lead Arkusze pogrupowane według szablonów. Najnowsze są na górze.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead')
 
   .gh-button-row
     = link_to new_story_group_activity_group_template_path(@story_group), class: 'gh-btn gh-btn--secondary' do
       %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      Nowy szablon
+      = t('.new_template')
 
 - if @index.any?
   - @index.templates.each do |template|
     = render 'template_panel', template: template, fresh_sheet_ids: @fresh_sheet_ids
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Nie masz jeszcze żadnego szablonu
-    %p.gh-lead
-      Szablon to zestaw kategorii, za które nagradzasz studentów. Z jednego
-      szablonu tworzysz potem kolejne arkusze — po jednym na zajęcia.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/activity_groups/new.html.haml b/app/views/activity_groups/new.html.haml
index a32b2e28..8dbb26d1 100644
--- a/app/views/activity_groups/new.html.haml
+++ b/app/views/activity_groups/new.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Nowy arkusz z szablonu #{@template.base_name}"
+- content_for :title, t('.page_title', name: @template.base_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/auth/passwordless/inbox.html.haml b/app/views/auth/passwordless/inbox.html.haml
index 8d2c9625..8478311f 100644
--- a/app/views/auth/passwordless/inbox.html.haml
+++ b/app/views/auth/passwordless/inbox.html.haml
@@ -1,16 +1,16 @@
-- content_for :title, 'Sprawdź skrzynkę'
-- waiting_label = 'Wyślij ponownie za %{time}'
-- idle_label    = 'Wyślij link ponownie'
+- content_for :title, t('.title')
+- waiting_label = t('.waiting', time: '%{time}')
+- idle_label    = t('.resend')
 
 .text-center
   .gh-icon-circle-lg.gh-octagon-clip.mx-auto
     %i.fa-solid.fa-envelope
-  %h1.gh-h1 Sprawdź skrzynkę
-  %p.gh-lead.mx-auto Wysłaliśmy link na adres
+  %h1.gh-h1= t('.title')
+  %p.gh-lead.mx-auto= t('.sent_to')
   %p.gh-email-display= @email
   %p.gh-small.mt-4
-    = "Link działa przez #{gh_minutes(LoginToken::EXPIRES_IN.in_minutes.to_i)}."
-    Jeśli go nie widzisz, zajrzyj do folderu Spam.
+    = t('.valid_for', minutes: gh_minutes(LoginToken::EXPIRES_IN.in_minutes.to_i))
+    = t('.spam')
 
   .gh-button-stack
     = button_to auth_passwordless_path,
@@ -27,4 +27,4 @@
       - else
         = idle_label
 
-    = link_to 'Zmień adres e-mail', new_auth_passwordless_path, class: 'gh-link-button'
+    = link_to t('.change_email'), new_auth_passwordless_path, class: 'gh-link-button'
diff --git a/app/views/auth/passwordless/new.html.haml b/app/views/auth/passwordless/new.html.haml
index bf2b2f54..d24d944d 100644
--- a/app/views/auth/passwordless/new.html.haml
+++ b/app/views/auth/passwordless/new.html.haml
@@ -1,23 +1,23 @@
-- content_for :title, 'Logowanie e-mailem'
+- content_for :title, t('.title')
 
 = link_to login_path, class: 'gh-link-button gh-back-link' do
   %i.fa-solid.fa-chevron-left
-  %span Inne sposoby logowania
+  %span= t('.back')
 
-%h1.gh-h1 Logowanie e-mailem
-%p.gh-lead Wyślemy Ci link do logowania. Hasło nie jest potrzebne.
+%h1.gh-h1= t('.title')
+%p.gh-lead= t('.lead')
 
 = form_with url: auth_passwordless_path, method: :post do |f|
   .gh-form-field
-    = f.label :email, 'Adres e-mail'
+    = f.label :email, t('.email')
     .gh-text-input
       = f.email_field :email,
-        placeholder: 'jan.nowak@example.com',
+        placeholder: t('.placeholder'),
         autocomplete: 'email',
         autofocus: true,
         required: true
 
   .gh-button-stack
-    %button.gh-btn{ type: 'submit' } Wyślij link
+    %button.gh-btn{ type: 'submit' }= t('.send')
 
 = render 'shared/register_prompt'
diff --git a/app/views/badges/_back.html.haml b/app/views/badges/_back.html.haml
index 726aac0e..a6491a67 100644
--- a/app/views/badges/_back.html.haml
+++ b/app/views/badges/_back.html.haml
@@ -8,10 +8,10 @@
   = badge_name(badge)
 
 %p.gh-badge-rule-text
-  %span Jak zdobyć
+  %span= t('.how')
   %span{ data: targets[:how] }= badge_rule(badge)
 
 - if flipper
-  %button.gh-card-flip-btn{ type: 'button', 'aria-label': "Pokaż odznakę #{badge.name}" }
+  %button.gh-card-flip-btn{ type: 'button', 'aria-label': t('.flip_label', name: badge.name) }
     %i.fa-solid.fa-arrows-rotate{ 'aria-hidden': 'true' }
-    Pokaż odznakę
+    = t('.flip')
diff --git a/app/views/badges/_confirm_destroy.html.haml b/app/views/badges/_confirm_destroy.html.haml
index e06c24de..2ab75bb2 100644
--- a/app/views/badges/_confirm_destroy.html.haml
+++ b/app/views/badges/_confirm_destroy.html.haml
@@ -1,24 +1,18 @@
-%h2#gh-del-title.gh-h2= "Usunąć odznakę „#{badge.name}”?"
-%p
-  Studenci, którzy mają tę odznakę, zachowają ją w historii, ale nikt nowy jej
-  nie dostanie.
+%h2#gh-del-title.gh-h2= t('.title', name: badge.name)
+%p= t('.body')
 
 - if unlocking_items.any?
-  - one = unlocking_items.one?
   %p.gh-warning-note{ role: 'alert' }
     %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-    %span
-      = "#{one ? 'Przedmiot' : 'Przedmioty'} #{gh_and_list(unlocking_items.map(&:name))}"
-      = one ? 'odblokowuje się tą odznaką' : 'odblokowują się tą odznaką'
-      = "i po usunięciu #{one ? 'kupi go' : 'kupią je'} tylko ci, którzy już ją mają."
+    %span= t('.unlocking', count: unlocking_items.size, items: gh_and_list(unlocking_items.map(&:name)))
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', edit_story_group_badge_path(@story_group, badge), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), edit_story_group_badge_path(@story_group, badge), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń odznakę', story_group_badge_path(@story_group, badge),
+  = button_to t('.remove'), story_group_badge_path(@story_group, badge),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/badges/_flip_card.html.haml b/app/views/badges/_flip_card.html.haml
index b1518343..c1f7ff7b 100644
--- a/app/views/badges/_flip_card.html.haml
+++ b/app/views/badges/_flip_card.html.haml
@@ -3,7 +3,7 @@
 - withdrawn   = local_assigns.fetch(:withdrawn, false)
 - targets     = local_assigns.fetch(:targets, {})
 
-- label = earned ? "Odznaka #{badge.name}" : "Odznaka #{badge.name}, jeszcze niezdobyta"
+- label = t(earned ? 'badges.flip_card.label' : 'badges.flip_card.label_unearned', name: badge.name)
 - card_data = targets[:flip].to_h
 - card_data.merge!(controller: 'badge-flip', action: 'click->badge-flip#toggle') if interactive
 
diff --git a/app/views/badges/_form.html.haml b/app/views/badges/_form.html.haml
index 02ce2808..28c6eb18 100644
--- a/app/views/badges/_form.html.haml
+++ b/app/views/badges/_form.html.haml
@@ -5,14 +5,16 @@
 
 %section.gh-panel.gh-page-header.gh-page-header--stacked
   %p.gh-breadcrumbs
-    = link_to 'Odznaki', story_group_badges_path(@story_group)
+    = link_to t('.breadcrumb'), story_group_badges_path(@story_group)
     %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
-    %span= editing ? (badge.name_was.presence || badge.name) : 'Nowa odznaka'
-  %h1.gh-h1= editing ? 'Edytuj odznakę' : 'Nowa odznaka'
-  %p.gh-lead
-    Podgląd obok pokazuje obie strony karty: zdobytą i jeszcze niezdobytą.
+    %span= editing ? (badge.name_was.presence || badge.name) : t('.new_title')
+  %h1.gh-h1= editing ? t('.edit_title') : t('.new_title')
+  %p.gh-lead= t('.lead')
 
-- form_data = { controller: 'badge-form', action: 'gh:image-crop->badge-form#art' }
+- form_data = { controller: 'badge-form', action: 'gh:image-crop->badge-form#art',
+                badge_form_name_placeholder_value: t('badges.helpers.name_placeholder'),
+                badge_form_rule_placeholder_value: t('badges.helpers.rule_placeholder'),
+                badge_form_discount_label_value: t('badges.helpers.discount', discount: '%{discount}'), }
 
 = form_with model: [@story_group, badge], data: form_data do |f|
 
@@ -22,19 +24,18 @@
         %p.gh-info-banner
           %i.fa-solid.fa-users{ 'aria-hidden': 'true' }
           %span
-            %b
-              = "#{holders} #{gh_plural(holders, 'student ma', 'studentów ma', 'studentów ma')} tę odznakę."
-            Zmiana zniżki od razu obejmie ich kolejne zakupy.
+            %b= t('.holders', count: holders)
+            = t('.holders_note')
 
       .gh-form-section
-        %h2.gh-h3 Karta odznaki
-        %p.gh-field-hint Tak odznaka wygląda w talii studenta i w oknie przyznawania.
+        %h2.gh-h3= t('.card')
+        %p.gh-field-hint= t('.card_hint')
 
         .gh-form-field
-          = f.label :name, 'Nazwa'
+          = f.label :name, t('shared.actions.name')
           .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:name)) }
             = f.text_field :name, maxlength: 50, autocomplete: 'off',
-              placeholder: 'np. Perfekcyjny Lot',
+              placeholder: t('.name_placeholder'),
               'aria-invalid': (error.call(:name) ? 'true' : nil),
               'aria-describedby': (error.call(:name) ? 'gh-badge-name-error' : nil),
               data: { badge_form_target: 'name', action: 'badge-form#refresh' }
@@ -44,10 +45,10 @@
               %span= error.call(:name)
 
         .gh-form-field
-          = f.label :didactic_description, 'Jak zdobyć'
+          = f.label :didactic_description, t('.rule')
           .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:didactic_description)) }
             = f.text_area :didactic_description, rows: 2, maxlength: 255,
-              placeholder: 'np. Co najmniej 3 wejściówki z rzędu bez błędów',
+              placeholder: t('.rule_placeholder'),
               'aria-invalid': (error.call(:didactic_description) ? 'true' : nil),
               'aria-describedby': (error.call(:didactic_description) ? 'gh-badge-rule-error' : nil),
               data: { badge_form_target: 'rule', action: 'badge-form#refresh' }
@@ -55,17 +56,15 @@
             %p#gh-badge-rule-error.gh-field-error{ role: 'alert' }
               %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
               %span= error.call(:didactic_description)
-          %span.gh-field-hint
-            Studenci widzą to na odwrocie odznaki, której jeszcze nie mają.
-            Pisz konkretnie.
+          %span.gh-field-hint= t('.rule_hint')
 
         .gh-form-field
           = f.label :story_description do
-            Opis fabularny
-            %small (opcjonalnie)
+            = t('.story')
+            %small= t('shared.actions.optional')
           .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:story_description)) }
             = f.text_area :story_description, rows: 2, maxlength: 255,
-              placeholder: 'np. Lot bez najmniejszej rysy',
+              placeholder: t('.story_placeholder'),
               'aria-invalid': (error.call(:story_description) ? 'true' : nil),
               'aria-describedby': (error.call(:story_description) ? 'gh-badge-story-error' : nil),
               data: { badge_form_target: 'story', action: 'badge-form#refresh' }
@@ -79,13 +78,11 @@
           refresh_action: 'badge-form#refresh'
 
       .gh-form-section
-        %h2.gh-h3 Zniżka w sklepie
-        %p.gh-field-hint
-          Działa tylko na przedmioty, które ją uwzględniają. Ustawiasz to
-          w formularzu przedmiotu.
+        %h2.gh-h3= t('.discount_section')
+        %p.gh-field-hint= t('.discount_hint')
 
         .gh-form-field
-          = f.label :discount, 'Zniżka w sklepie'
+          = f.label :discount, t('.discount')
           .gh-price-field-row
             .gh-text-input.gh-text-input--numeric{ class: ('gh-text-input--invalid' if error.call(:discount)) }
               = f.number_field :discount, min: 0, max: 100, step: 1,
@@ -101,34 +98,32 @@
 
         - using = editing ? shelf.dependent_items(badge) : []
         - if using.any?
-          %p.gh-form-label.gh-label--spaced Uwzględniają ją
+          %p.gh-form-label.gh-label--spaced= t('.used_by')
           %ul.gh-badge-usage-list
             - using.each do |item|
               %li
                 = render 'layouts/item_thumb', item: item
                 = item.name
         - else
-          %p.gh-explainer-note Na razie żaden przedmiot jej nie uwzględnia.
+          %p.gh-explainer-note= t('.unused')
 
       - if editing
         .gh-form-section
-          %h2.gh-h3 Usuwanie
-          %p.gh-field-hint
-            Odznaka zniknie z listy i z okna przyznawania. Studenci, którzy ją
-            mają, zachowają ją w historii.
+          %h2.gh-h3= t('shared.actions.removal')
+          %p.gh-field-hint= t('.removal_hint')
           .gh-button-row
             = link_to confirm_destroy_story_group_badge_path(@story_group, badge),
               class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
               %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-              Usuń odznakę
+              = t('.remove')
 
-    %aside.gh-preview-column{ 'aria-label': 'Podgląd' }
+    %aside.gh-preview-column{ 'aria-label': t('shared.actions.preview') }
       = render 'preview', badge: badge
 
   .gh-panel.gh-form-actions-bar
-    = link_to 'Anuluj', story_group_badges_path(@story_group), class: 'gh-link-button'
+    = link_to t('shared.actions.cancel'), story_group_badges_path(@story_group), class: 'gh-link-button'
     %span.gh-form-actions-spacer
     %button.gh-btn{ type: 'submit' }
       - unless editing
         %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      = editing ? 'Zapisz zmiany' : 'Dodaj odznakę'
+      = editing ? t('shared.actions.save_changes') : t('.create')
diff --git a/app/views/badges/_front.html.haml b/app/views/badges/_front.html.haml
index 9ad1cac9..198e4618 100644
--- a/app/views/badges/_front.html.haml
+++ b/app/views/badges/_front.html.haml
@@ -12,7 +12,7 @@
 
 - if local_assigns[:withdrawn]
   .gh-card-tags
-    %span.gh-tag.gh-tag--removed Usunięta z listy
+    %span.gh-tag.gh-tag--removed= t('.removed')
 
 %p.gh-rule-text{ class: ('gh-placeholder-text' if badge.didactic_description.blank?), data: targets[:rules] }
   = badge_rule(badge)
@@ -24,6 +24,6 @@
   %span.gh-tag.gh-tag--discount{ hidden: discount.nil?, data: targets[:tag] }= discount
   - if flipper
     %button.gh-card-flip-btn{ type: 'button',
-                        'aria-label': "Pokaż, jak zdobyć odznakę #{badge.name}" }
+                        'aria-label': t('.flip_label', name: badge.name) }
       %i.fa-solid.fa-arrows-rotate{ 'aria-hidden': 'true' }
-      Jak zdobyć
+      = t('.flip')
diff --git a/app/views/badges/_preview.html.haml b/app/views/badges/_preview.html.haml
index 8e9c5950..a5179633 100644
--- a/app/views/badges/_preview.html.haml
+++ b/app/views/badges/_preview.html.haml
@@ -9,26 +9,26 @@
 
 %details.gh-preview-details{ open: true }
   %summary
-    Podgląd karty
+    = t('.summary')
     %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
   %section.gh-panel.gh-preview-panel
-    %h3 Tak zobaczą to studenci
+    %h3= t('.students_view')
 
-    .gh-segmented-toggle-2.gh-octagon-clip{ role: 'group', 'aria-label': 'Strona karty' }
+    .gh-segmented-toggle-2.gh-octagon-clip{ role: 'group', 'aria-label': t('.side') }
       %button{ type: 'button', 'aria-pressed': 'true', value: 'won',
                data: { action: 'badge-form#side', badge_form_target: 'side' } }
-        Zdobyta
+        = t('.earned')
       %button{ type: 'button', 'aria-pressed': 'false', value: 'lost',
                data: { action: 'badge-form#side', badge_form_target: 'side' } }
-        Jeszcze niezdobyta
+        = t('.unearned')
 
     .gh-preview-flip-card
       = render 'flip_card', badge: badge, earned: true,
         interactive: false, targets: targets
 
   %section.gh-panel.gh-preview-panel
-    %h3 W oknie przyznawania
+    %h3= t('.picker')
     .gh-preview-thumb-row
       = render 'badge_thumb', badge: badge,
         inner_data: { badge_form_target: 'thumbArt' }
diff --git a/app/views/badges/_student_deck.html.haml b/app/views/badges/_student_deck.html.haml
index 51d10899..c454dd1f 100644
--- a/app/views/badges/_student_deck.html.haml
+++ b/app/views/badges/_student_deck.html.haml
@@ -1,10 +1,7 @@
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Odznaki
-    %p.gh-lead
-      = "Masz #{shelf.earned_count} z #{shelf.size}."
-      Odznaki przyznaje prowadzący. Na odwrocie każdej niezdobytej znajdziesz,
-      jak ją zdobyć.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead', earned: shelf.earned_count, total: shelf.size)
 
 - if shelf.any?
   .gh-card-grid.gh-card-grid--compact
@@ -15,7 +12,5 @@
         withdrawn: slot.withdrawn?
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 W tej grupie nie ma jeszcze odznak
-    %p.gh-lead
-      Prowadzący ich nie dodał. Kiedy się pojawią, zobaczysz tu, co trzeba
-      zrobić, żeby je zdobyć.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/badges/_teacher_grid.html.haml b/app/views/badges/_teacher_grid.html.haml
index fcc6de68..7a1e625b 100644
--- a/app/views/badges/_teacher_grid.html.haml
+++ b/app/views/badges/_teacher_grid.html.haml
@@ -1,14 +1,12 @@
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Odznaki
-    %p.gh-lead
-      = "#{shelf.size} #{gh_plural(shelf.size, 'odznaka', 'odznaki', 'odznak')}."
-      Przyznajesz je ręcznie, z tej listy albo z listy studentów.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead', count: shelf.size)
 
   .gh-button-row
     = link_to new_story_group_badge_path(@story_group), class: 'gh-btn' do
       %i.fa-solid.fa-plus
-      Nowa odznaka
+      = t('.new')
 
 - if shelf.any?
   .gh-badge-grid--teacher
@@ -34,14 +32,12 @@
             .gh-card-footer
               %span.gh-card-meta= badge_holders_line(slot.holders)
               .gh-card-actions
-                = link_to 'Przyznaj', story_group_students_path(@story_group),
+                = link_to t('.award'), story_group_students_path(@story_group),
                   class: 'gh-btn gh-btn--small'
                 = link_to edit_story_group_badge_path(@story_group, badge),
-                  class: 'gh-icon-button', 'aria-label': "Edytuj odznakę #{badge.name}" do
+                  class: 'gh-icon-button', 'aria-label': t('.edit_label', name: badge.name) do
                   %i.fa-solid.fa-pen{ 'aria-hidden': 'true' }
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Nie ma jeszcze żadnych odznak
-    %p.gh-lead
-      Dodaj odznaki, żeby mieć czym nagradzać to, czego nie widać w punktach.
-      Przyznajesz je ręcznie, a każda może dawać zniżkę w sklepie.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/badges/confirm_destroy.html.haml b/app/views/badges/confirm_destroy.html.haml
index 16b7407a..7391b1c4 100644
--- a/app/views/badges/confirm_destroy.html.haml
+++ b/app/views/badges/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń odznakę #{@badge.name}"
+- content_for :title, t('.page_title', name: @badge.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/badges/edit.html.haml b/app/views/badges/edit.html.haml
index 432b26ba..c6544703 100644
--- a/app/views/badges/edit.html.haml
+++ b/app/views/badges/edit.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, "Edytuj odznakę - #{@badge.name}"
+- content_for :title, t('.page_title', name: @badge.name)
 
 = render 'form', badge: @badge, shelf: @shelf
diff --git a/app/views/badges/index.html.haml b/app/views/badges/index.html.haml
index 2878a01f..2c36d44b 100644
--- a/app/views/badges/index.html.haml
+++ b/app/views/badges/index.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Odznaki'
+- content_for :title, t('.title')
 
 - if @shelf.membership
   = render 'student_deck', shelf: @shelf
diff --git a/app/views/badges/new.html.haml b/app/views/badges/new.html.haml
index 2b4eaf97..0235db66 100644
--- a/app/views/badges/new.html.haml
+++ b/app/views/badges/new.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, 'Nowa odznaka'
+- content_for :title, t('.page_title')
 
 = render 'form', badge: @badge, shelf: @shelf
diff --git a/app/views/currency_adjustments/_form.html.haml b/app/views/currency_adjustments/_form.html.haml
index e6a69a70..0f5050ea 100644
--- a/app/views/currency_adjustments/_form.html.haml
+++ b/app/views/currency_adjustments/_form.html.haml
@@ -2,29 +2,27 @@
 - error   = form.error_for(:amount)
 - rungs   = @story_group.ranks.by_threshold.map { |r| { v: r.required_currency_value.to_i, n: r.name } }
 
-- add_note  = 'Dodanie podnosi też sumę zebranych, więc może podnieść rangę.'
-- take_note = 'Odjęcie zmniejsza tylko to, co student ma do wydania. Suma zebranych i ranga zostają bez zmian.'
 - form_data = { controller: 'currency-adjust',
                 turbo_frame: (@in_modal ? 'modal' : nil),
                 currency_adjust_balance_value: form.balance,
                 currency_adjust_total_value: form.total,
                 currency_adjust_rungs_value: rungs.to_json,
-                currency_adjust_over_value: "Student ma tylko #{form.balance} do wydania.",
-                currency_adjust_unchanged_value: 'bez zmian',
-                currency_adjust_add_value: 'Dodaj',
-                currency_adjust_take_value: 'Odejmij',
-                currency_adjust_blank_value: 'Podaj kwotę',
-                currency_adjust_add_note_value: add_note,
-                currency_adjust_take_note_value: take_note, }
+                currency_adjust_over_value: t('.over', balance: form.balance),
+                currency_adjust_unchanged_value: t('.unchanged'),
+                currency_adjust_add_value: t('shared.actions.add'),
+                currency_adjust_take_value: t('.take'),
+                currency_adjust_blank_value: t('.blank'),
+                currency_adjust_add_note_value: t('.add_note'),
+                currency_adjust_take_note_value: t('.take_note'), }
 
 = form_with url: story_group_student_currency_adjustment_path(@story_group, student),
   method: :post, scope: :currency_adjustment, data: form_data do |f|
 
-  %h2#gh-adjust-title.gh-h2 Koryguj walutę
-  %p= "#{student.display_name} ma teraz #{form.balance} do wydania."
+  %h2#gh-adjust-title.gh-h2= t('.title')
+  %p= t('.lead', name: student.display_name, balance: form.balance)
 
-  .gh-segmented-toggle-3.gh-octagon-clip{ role: 'radiogroup', 'aria-label': 'Rodzaj korekty' }
-    - [[1, 'Dodaj'], [-1, 'Odejmij']].each do |value, label|
+  .gh-segmented-toggle-3.gh-octagon-clip{ role: 'radiogroup', 'aria-label': t('.kind_label') }
+    - [[1, t('shared.actions.add')], [-1, t('.take')]].each do |value, label|
       %label.gh-segmented-toggle-3-option
         = f.radio_button :sign, value,
           checked: (form.sign == value),
@@ -32,7 +30,7 @@
         %span= label
 
   .gh-form-field
-    = f.label :amount, 'Ile'
+    = f.label :amount, t('.amount')
     .gh-price-field-row
       .gh-text-input.gh-text-input--numeric{ class: ('gh-text-input--invalid' if error), data: { currency_adjust_target: 'box' } }
         = f.number_field :amount, min: 1, step: 1, placeholder: '0', autocomplete: 'off',
@@ -49,29 +47,25 @@
 
   - shown = form.value.present? && error.nil?
   %dl.gh-adjustment-preview{ hidden: !shown, data: { currency_adjust_target: 'preview' } }
-    %dt Do wydania
+    %dt= t('.balance')
     %dd{ data: { currency_adjust_target: 'balance' } }= "#{form.balance} → #{form.new_balance}"
-    %dt Zebrane łącznie
+    %dt= t('.total')
     %dd{ data: { currency_adjust_target: 'total' } }
-      = form.total_changed? ? "#{form.total} → #{form.new_total}" : "#{form.total} (bez zmian)"
-    %dt.gh-cprev2-r{ hidden: !form.rank_changed?, data: { currency_adjust_target: 'rankLabel' } } Ranga
+      = form.total_changed? ? "#{form.total} → #{form.new_total}" : t('.total_unchanged', total: form.total)
+    %dt.gh-cprev2-r{ hidden: !form.rank_changed?, data: { currency_adjust_target: 'rankLabel' } }= t('.rank')
     %dd.gh-cprev2-r{ hidden: !form.rank_changed?, data: { currency_adjust_target: 'rank' } }
       = "#{form.current_rank&.name || '—'} → #{form.new_rank&.name || '—'}"
 
   %p.gh-small.gh-adjustment-preview-note{ hidden: !shown, data: { currency_adjust_target: 'note' } }
-    - if form.positive?
-      Dodanie podnosi też sumę zebranych, więc może podnieść rangę.
-    - else
-      Odjęcie zmniejsza tylko to, co student ma do wydania. Suma zebranych
-      i ranga zostają bez zmian.
+    = form.positive? ? t('.add_note') : t('.take_note')
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
     - else
-      = link_to 'Anuluj', story_group_student_path(@story_group, student), class: 'gh-btn gh-btn--secondary'
+      = link_to t('shared.actions.cancel'), story_group_student_path(@story_group, student), class: 'gh-btn gh-btn--secondary'
     %button.gh-btn{ type: 'submit', data: { currency_adjust_target: 'submit' } }
       - if form.value.present?
-        = "#{form.positive? ? 'Dodaj' : 'Odejmij'} #{form.value}"
+        = t(form.positive? ? '.submit_add' : '.submit_take', value: form.value)
       - else
-        Podaj kwotę
+        = t('.blank')
diff --git a/app/views/currency_adjustments/new.html.haml b/app/views/currency_adjustments/new.html.haml
index d0a08b54..42ba7eba 100644
--- a/app/views/currency_adjustments/new.html.haml
+++ b/app/views/currency_adjustments/new.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Koryguj walutę - #{@student.display_name}"
+- content_for :title, t('.page_title', name: @student.display_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/currency_transactions/_ledger.html.haml b/app/views/currency_transactions/_ledger.html.haml
index 62a69ce3..06636e48 100644
--- a/app/views/currency_transactions/_ledger.html.haml
+++ b/app/views/currency_transactions/_ledger.html.haml
@@ -7,13 +7,13 @@
     %span.gh-ledger-header-spacer
     %span.gh-small= summary
 
-%div{ role: 'table', 'aria-label': 'Historia waluty' }
+%div{ role: 'table', 'aria-label': t('.table_label') }
   .gh-ledger-row.gh-ledger-row--header{ role: 'row' }
-    %span{ role: 'columnheader' } Kwota
-    %span{ role: 'columnheader' } Typ
-    %span{ role: 'columnheader' } Za co
-    %span{ role: 'columnheader' } Kiedy
-    %span.gh-ledger-cell--right{ role: 'columnheader' } Saldo po
+    %span{ role: 'columnheader' }= t('.columns.amount')
+    %span{ role: 'columnheader' }= t('.columns.kind')
+    %span{ role: 'columnheader' }= t('.columns.source')
+    %span{ role: 'columnheader' }= t('.columns.when')
+    %span.gh-ledger-cell--right{ role: 'columnheader' }= t('.columns.balance_after')
 
   - entries.each do |entry|
     .gh-ledger-row{ role: 'row' }
@@ -22,7 +22,7 @@
       %span.gh-ledger-source{ role: 'cell' }
         = entry.title
         - if entry.withdrawn?
-          %span.gh-tag.gh-tag--removed Usunięty z oferty
+          %span.gh-tag.gh-tag--removed= t('.withdrawn')
         - if entry.context.present?
           %small= entry.context
       %span.gh-small.gh-ledger-date{ role: 'cell' }= ledger_when(entry)
diff --git a/app/views/currency_transactions/index.html.haml b/app/views/currency_transactions/index.html.haml
index 97aa9964..1354b668 100644
--- a/app/views/currency_transactions/index.html.haml
+++ b/app/views/currency_transactions/index.html.haml
@@ -1,24 +1,22 @@
-- content_for :title, 'Historia waluty'
+- content_for :title, t('.title')
 - path_for = ->(kind) { story_group_student_currency_transactions_path(@story_group, @student, kind: kind) }
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Historia waluty
+    %h1.gh-h1= t('.title')
     %p.gh-lead= ledger_balance_sentence(@ledger)
 
   .gh-button-row
     = link_to story_group_shop_index_path(@story_group), class: 'gh-btn gh-btn--secondary' do
       %i.fa-solid.fa-bag-shopping{ 'aria-hidden': 'true' }
-      Przejdź do sklepu
+      = t('.go_to_shop')
 
 - if @ledger.any?
   %section.gh-panel.gh-tab-panel
     = render 'currency_transactions/ledger', ledger: @ledger, kind: @kind,
       path_for: path_for,
-      empty_message: 'Nie masz jeszcze wpisów tego typu.'
+      empty_message: t('.empty_kind')
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Pierwsze wpisy pojawią się po zajęciach
-    %p.gh-lead
-      Prowadzący przyznaje walutę za obecność, punktualność i aktywność.
-      Wszystko, co zdobędziesz i wydasz, zapisze się tutaj.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/home/_capacity_bar.html.haml b/app/views/home/_capacity_bar.html.haml
index b60baa28..427c3e6f 100644
--- a/app/views/home/_capacity_bar.html.haml
+++ b/app/views/home/_capacity_bar.html.haml
@@ -1,5 +1,5 @@
 - if max.nil?
-  %span.gh-small= "#{members} #{gh_plural(members, 'konto', 'konta', 'kont')} · bez limitu"
+  %span.gh-small= t('home.capacity_bar.unlimited', count: members)
 - else
   .gh-capacity-bar
     .gh-progress-bar.gh-octagon-clip{ class: ('gh-progress-bar--full' if full),
@@ -7,6 +7,6 @@
                        'aria-valuemin': 0,
                        'aria-valuemax': max,
                        'aria-valuenow': members,
-                       'aria-label':    'Zajęte miejsca', }
+                       'aria-label':    t('home.capacity_bar.label'), }
       %i.gh-octagon-clip{ style: "--gh-p: #{percent}%" }
     %span.gh-small= "#{members} / #{max}"
diff --git a/app/views/home/_global_admin_start.html.haml b/app/views/home/_global_admin_start.html.haml
index 19d7d234..ff1c8510 100644
--- a/app/views/home/_global_admin_start.html.haml
+++ b/app/views/home/_global_admin_start.html.haml
@@ -5,75 +5,69 @@
     %h1.gh-h1= home_greeting(@current_user)
     %p.gh-lead
       - if organizations.empty?
-        Nie ma jeszcze żadnej organizacji. Utwórz pierwszą, żeby nowe konta miały gdzie trafić.
+        = t('.no_organizations_lead')
       - elsif @dashboard.attention?
-        = "#{organizations.size} #{gh_plural(organizations.size, 'organizacja', 'organizacje', 'organizacji')} —"
-        część z nich potrzebuje Twojej uwagi.
+        = t('.attention_lead', count: organizations.size)
       - else
-        = "#{organizations.size} #{gh_plural(organizations.size, 'organizacja', 'organizacje', 'organizacji')}."
-        Wszystkie mają administratora i wolne miejsca.
+        = t('.fine_lead', count: organizations.size)
 
   = link_to new_organization_path, class: 'gh-btn', data: { turbo_frame: 'modal' } do
     %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-    Utwórz organizację
+    = t('.create')
 
 - if organizations.any?
-  = render 'stat_tiles', tiles: @dashboard.stat_tiles, label: 'Podsumowanie organizacji'
+  = render 'stat_tiles', tiles: @dashboard.stat_tiles, label: t('.stats_label')
 
   .gh-dashboard-layout
     %section.gh-panel.gh-recent-purchases-panel{ 'aria-labelledby': 'gh-orgs-title' }
-      %h2#gh-orgs-title.gh-h2 Organizacje
+      %h2#gh-orgs-title.gh-h2= t('.organizations')
       .gh-start-org-list
         - organizations.each do |org|
           = link_to organization_path(org.organization), class: 'gh-start-org-row' do
             %span.gh-name-cell
               %b= org.organization.name
               %small
-                = "#{org.admins} #{gh_plural(org.admins, 'administrator', 'administratorów', 'administratorów')}"
+                = t('.admins', count: org.admins)
                 - if org.pending_admins.positive?
-                  = "· #{org.pending_admins} #{gh_plural(org.pending_admins, 'zaproszenie czeka', 'zaproszenia czekają', 'zaproszeń czeka')}"
+                  = "· #{t('.pending_admins', count: org.pending_admins)}"
             = render 'capacity_bar', members: org.member_count, max: org.organization.max_members,
                                      percent: org.fill_percent, full: org.full?
-      = link_to 'Wszystkie organizacje', organizations_path, class: 'gh-btn gh-btn--secondary gh-start-more'
+      = link_to t('.all_organizations'), organizations_path, class: 'gh-btn gh-btn--secondary gh-start-more'
 
     .gh-dashboard-side-column
       - if @dashboard.attention?
         %section.gh-card.gh-todo-card
           .gh-card-frame
             .gh-card-inset
-              %p.gh-page-kicker Wymaga uwagi
+              %p.gh-page-kicker= t('.attention')
               %ul.gh-start-attention-list
                 - @dashboard.without_admin.each do |org|
                   %li
                     = link_to org.organization.name, organization_path(org.organization)
-                    %small Brak administratora
+                    %small= t('.no_admin')
                     = link_to new_admin_organization_path(org.organization), class: 'gh-btn gh-btn--secondary gh-btn--small',
                       data: { turbo_frame: 'modal' } do
                       %i.fa-solid.fa-user-shield{ 'aria-hidden': 'true' }
-                      Dodaj
+                      = t('.add')
                 - @dashboard.nearly_full.each do |org|
                   %li
                     = link_to org.organization.name, organization_path(org.organization)
-                    %small= org.full? ? 'Brak wolnych miejsc' : "Zostało #{org.free} #{gh_plural(org.free, 'miejsce', 'miejsca', 'miejsc')}"
+                    %small= org.full? ? t('.no_free_seats') : t('.free_seats', count: org.free)
                     = link_to edit_organization_path(org.organization), class: 'gh-btn gh-btn--secondary gh-btn--small',
                       data: { turbo_frame: 'modal' } do
                       %i.fa-solid.fa-pen{ 'aria-hidden': 'true' }
-                      Limit
+                      = t('.limit')
       - else
         %section.gh-panel.gh-my-groups-panel
-          %h2.gh-h2 Wszystko w porządku
-          %p.gh-small Każda organizacja ma administratora i wolne miejsca.
+          %h2.gh-h2= t('.fine_title')
+          %p.gh-small= t('.fine_body')
 
       %section.gh-panel.gh-my-groups-panel
-        %h2.gh-h2 Jak to działa
-        %p.gh-small
-          Każdy, kto zaloguje się przez USOS, trafia do organizacji
-          #{Organization::USOS_NAME}. Nie ma ona limitu miejsc i nie można jej
-          usunąć. Do pozostałych organizacji konta dodają ich administratorzy.
+        %h2.gh-h2= t('.how_title')
+        %p.gh-small= t('.how_body', usos: Organization::USOS_NAME)
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Zacznij od pierwszej organizacji
-    %p.gh-lead
-      Ustaw limit kont i dodaj administratora — on zaprosi resztę osób.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_lead')
     .gh-button-row
-      = link_to 'Utwórz organizację', new_organization_path, class: 'gh-btn', data: { turbo_frame: 'modal' }
+      = link_to t('.create'), new_organization_path, class: 'gh-btn', data: { turbo_frame: 'modal' }
diff --git a/app/views/home/_organization_admin_start.html.haml b/app/views/home/_organization_admin_start.html.haml
index 0cb76d74..b01af678 100644
--- a/app/views/home/_organization_admin_start.html.haml
+++ b/app/views/home/_organization_admin_start.html.haml
@@ -3,9 +3,7 @@
 - if organization.nil?
   %section.gh-panel.gh-empty-state
     %h1.gh-h1= home_greeting(@current_user)
-    %p.gh-lead
-      Twoje konto administratora nie jest przypisane do żadnej organizacji.
-      Skontaktuj się z administratorem systemu.
+    %p.gh-lead= t('.no_organization')
 - else
   %section.gh-panel.gh-page-header
     .gh-page-header-text
@@ -13,27 +11,25 @@
       %h1.gh-h1= home_greeting(@current_user)
       %p.gh-lead
         - if @dashboard.full?
-          Organizacja nie ma wolnych miejsc — nowe osoby nie dołączą, dopóki
-          ktoś nie zostanie usunięty albo limit nie wzrośnie.
+          = t('.full_lead')
         - elsif @dashboard.pending_users.any?
-          - pending = @dashboard.pending_users.size
-          = "#{pending} #{gh_plural(pending, 'osoba jeszcze nie przyjęła', 'osoby jeszcze nie przyjęły', 'osób jeszcze nie przyjęło')} zaproszenia."
+          = t('.pending_lead', count: @dashboard.pending_users.size)
         - else
           = organization_capacity_lead(organization, @dashboard.member_count)
 
     .gh-button-row
       = link_to organization_path(organization), class: 'gh-btn gh-btn--secondary' do
         %i.fa-solid.fa-users{ 'aria-hidden': 'true' }
-        Użytkownicy
+        = t('.users')
       = link_to new_user_organization_path(organization), class: 'gh-btn', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-user-plus{ 'aria-hidden': 'true' }
-        Dodaj użytkownika
+        = t('.add_user')
 
-  = render 'stat_tiles', tiles: @dashboard.stat_tiles, label: 'Podsumowanie organizacji'
+  = render 'stat_tiles', tiles: @dashboard.stat_tiles, label: t('.stats_label')
 
   .gh-dashboard-layout
     %section.gh-panel.gh-recent-purchases-panel{ 'aria-labelledby': 'gh-recent-users-title' }
-      %h2#gh-recent-users-title.gh-h2 Ostatnio dodani
+      %h2#gh-recent-users-title.gh-h2= t('.recent')
       - if @dashboard.recent_users.any?
         .gh-start-org-list
           - @dashboard.recent_users.each do |user|
@@ -41,31 +37,27 @@
               = render 'organizations/person', user: user
               %span.gh-teacher-role
                 = user_role_label(user.role)
-                %small= user.first_login? ? 'Zaproszenie wysłane' : "Dodano #{user.created_at.strftime('%d.%m.%Y')}"
-        = link_to 'Wszyscy użytkownicy', organization_path(organization), class: 'gh-btn gh-btn--secondary gh-start-more'
+                %small= user.first_login? ? t('.invited') : t('.added', when: gh_when(user.created_at))
+        = link_to t('.all_users'), organization_path(organization), class: 'gh-btn gh-btn--secondary gh-start-more'
       - else
-        %p.gh-small
-          Nikogo tu jeszcze nie ma. Dodaj studentów i nauczycieli albo poczekaj,
-          aż zalogują się przez uczelnię.
+        %p.gh-small= t('.nobody')
 
     .gh-dashboard-side-column
       %section.gh-panel.gh-my-groups-panel
-        %h2.gh-h2 Miejsca
+        %h2.gh-h2= t('.seats')
         = render 'capacity_bar', members: @dashboard.member_count, max: organization.max_members,
                                  percent: @dashboard.fill_percent, full: @dashboard.full?
         %p.gh-small
           - if organization.unlimited?
-            Ta organizacja nie ma limitu miejsc. Każdy, kto zaloguje się przez
-            USOS, trafia tutaj automatycznie.
+            = t('.unlimited_note')
           - else
-            Limit ustala administrator systemu. Każde konto, także administratora,
-            zajmuje jedno miejsce.
+            = t('.limited_note')
 
       - if @dashboard.pending_users.any?
         %section.gh-card.gh-todo-card
           .gh-card-frame
             .gh-card-inset
-              %p.gh-page-kicker Czeka na przyjęcie zaproszenia
+              %p.gh-page-kicker= t('.pending_title')
               %ul.gh-start-attention-list
                 - @dashboard.pending_users.first(Dashboard::OrganizationAdmin::RECENT_LIMIT).each do |user|
                   %li
diff --git a/app/views/home/_student_start.html.haml b/app/views/home/_student_start.html.haml
index 890e0162..b7b7615e 100644
--- a/app/views/home/_student_start.html.haml
+++ b/app/views/home/_student_start.html.haml
@@ -2,13 +2,8 @@
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Cześć, #{@current_user.full_name.to_s.split(' ').first}
-    %p.gh-lead
-      - if groups.any?
-        = "Należysz do #{groups.size} #{gh_plural(groups.size, 'grupy', 'grup', 'grup')}."
-        Waluta, rangi i odznaki są osobne w każdej z nich.
-      - else
-        Nie należysz jeszcze do żadnej grupy. Poproś prowadzącego o kod i dołącz poniżej.
+    %h1.gh-h1= t('.greeting', name: @current_user.full_name.to_s.split(' ').first)
+    %p.gh-lead= groups.any? ? t('.groups_lead', count: groups.size) : t('.no_groups_lead')
 
 .gh-group-card-grid
   - groups.each do |group|
@@ -26,19 +21,18 @@
             %h2.gh-card-name= story_group.name
 
           - if group.fresh?
-            %p.gh-explainer-note
-              = "Dopiero zaczynasz. Pierwsze #{story_group.currency_name} zdobędziesz na zajęciach."
+            %p.gh-explainer-note= t('.fresh', currency: story_group.currency_name)
 
           %dl.gh-group-card-stats
             %div
-              %dt Do wydania
+              %dt= t('.to_spend')
               %dd
                 = render 'layouts/currency_token', story_group: story_group
                 = group.balance
                 %small= story_group.currency_name
 
             %div
-              %dt Życia
+              %dt= t('.lives')
               %dd
                 %span.gh-lives-badge{ class: ('gh-lives-badge--zero' if group.lives.zero?) }
                   %i.fa-solid.fa-heart{ 'aria-hidden': 'true' }
@@ -46,43 +40,42 @@
 
             .gh-stat-span-full
               %dt
-                Ranga:
-                %b= group.rank&.name || 'brak'
+                = t('.rank')
+                %b= group.rank&.name || t('.no_rank')
               - if group.next_rank
                 %dd.gh-rank-progress-target
-                  = "#{group.total} z #{group.next_threshold} do rangi #{group.next_rank.name}"
+                  = t('.to_next', total: group.total, needed: group.next_threshold, rank: group.next_rank.name)
               - else
-                %dd.gh-rank-progress-target
-                  = "#{group.total} zebranych. To najwyższa ranga."
+                %dd.gh-rank-progress-target= t('.top', total: group.total)
               .gh-progress-bar.gh-octagon-clip{ role: 'progressbar',
                        'aria-valuemin': 0,
                        'aria-valuemax': group.next_threshold.positive? ? group.next_threshold : group.total,
                        'aria-valuenow': group.total,
-                       'aria-label': "Postęp do następnej rangi w grupie #{story_group.name}" }
+                       'aria-label': t('.progress_label', name: story_group.name) }
                 %i.gh-octagon-clip{ style: "--gh-p: #{gh_percent(group.total, group.next_threshold)}%" }
 
             %div
-              %dt Odznaki
+              %dt= t('.badges')
               %dd
                 = group.badges_earned
-                %small= "z #{group.badges_total}"
+                %small= t('.badges_of', total: group.badges_total)
 
           .gh-card-footer
-            = link_to 'Otwórz grupę', story_group_path(story_group), class: 'gh-btn'
+            = link_to t('.open_group'), story_group_path(story_group), class: 'gh-btn'
             = link_to story_group_shop_index_path(story_group), class: 'gh-btn gh-btn--secondary' do
               %i.fa-solid.fa-bag-shopping
-              Sklep
+              = t('.shop')
 
   .gh-panel.gh-join-code-card
-    %h2.gh-h3 Masz kod od prowadzącego?
-    %p.gh-small Kod ma 6 znaków. Możesz też zeskanować kod QR aparatem telefonu.
+    %h2.gh-h3= t('.have_code')
+    %p.gh-small= t('.code_hint')
     = link_to new_join_path, class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-plus
-      Dołącz do grupy
+      = t('.join')
 
 - if @dashboard.feed.any?
   %section.gh-panel.gh-activity-feed
-    %h2.gh-h2 Ostatnio we wszystkich grupach
+    %h2.gh-h2= t('.feed')
     %ul.gh-ledger-list
       - @dashboard.feed.each do |entry|
         - tone = entry.reward? ? 'earn' : (entry.purchase? ? 'spend' : nil)
@@ -90,6 +83,6 @@
           %span{ class: "gh-activity-feed-row-marker #{"gh-activity-feed-row-marker--#{tone}" if tone}", 'aria-hidden': 'true' }
           %span.gh-activity-feed-row-text
             = gh_feed_title(entry)
-            %small= "#{entry.student.story_group.name}, #{gh_when(entry.created_at)}"
+            %small= t('.feed_meta', group: entry.student.story_group.name, when: gh_when(entry.created_at))
           %span{ class: "gh-activity-feed-row-amount #{"gh-activity-feed-row-amount--#{tone}" if tone}" }
             = entry.amount.positive? ? "+#{entry.amount}" : entry.amount
diff --git a/app/views/home/_teacher_start.html.haml b/app/views/home/_teacher_start.html.haml
index 09e56f30..04cdbb23 100644
--- a/app/views/home/_teacher_start.html.haml
+++ b/app/views/home/_teacher_start.html.haml
@@ -3,24 +3,23 @@
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Dzień dobry, #{@current_user.full_name.to_s.split(' ').first}
+    %h1.gh-h1= t('.greeting', name: @current_user.full_name.to_s.split(' ').first)
     %p.gh-lead
       - if recent.any?
-        - group_count = @dashboard.recent_group_count
-        = "Od wczoraj studenci kupili #{recent.size} #{gh_plural(recent.size, 'przedmiot', 'przedmioty', 'przedmiotów')}"
-        = "w #{group_count} #{gh_plural(group_count, 'grupie', 'grupach', 'grupach')}."
+        = t('.recent_lead', items:  t('.recent_items', count: recent.size),
+                            groups: t('.recent_groups', count: @dashboard.recent_group_count))
       - elsif groups.any?
-        Od wczoraj nikt nic nie kupił. Zajrzyj do swoich grup poniżej.
+        = t('.quiet_lead')
       - else
-        Nie prowadzisz jeszcze żadnej grupy. Utwórz pierwszą, żeby zacząć.
+        = t('.no_groups_lead')
 
 .gh-dashboard-layout
   %section.gh-panel.gh-recent-purchases-panel{ 'aria-labelledby': 'gh-purch-title' }
-    %h2#gh-purch-title.gh-h2 Ostatnie zakupy
+    %h2#gh-purch-title.gh-h2= t('.purchases')
 
     - if groups.size > 1
-      .gh-purchase-filter-bar{ role: 'group', 'aria-label': 'Pokaż zakupy z grupy' }
-        = link_to 'Wszystkie grupy', home_path, class: 'gh-purchase-filter-chip',
+      .gh-purchase-filter-bar{ role: 'group', 'aria-label': t('.filter') }
+        = link_to t('.all_groups'), home_path, class: 'gh-purchase-filter-chip',
           'aria-current': @dashboard.filter.nil?.to_s
         - groups.each do |group|
           = link_to home_path(group: group.story_group.id), class: 'gh-purchase-filter-chip',
@@ -32,13 +31,13 @@
       - Dashboard::Teacher::DAYS.each do |day|
         - rows = @dashboard.purchases_on(day)
         - next if rows.empty?
-        %h3.gh-purchase-day-label= day
+        %h3.gh-purchase-day-label= t("home.days.#{day}")
         %ul.gh-purchase-list
           - rows.each do |purchase|
             %li.gh-purchase-row
               = render 'layouts/item_thumb', item: purchase.item
               %span.gh-purchase-row-main
-                %b= purchase.item&.name || 'Przedmiot usunięty z oferty'
+                %b= purchase.item&.name || t('.removed_item')
                 %span= purchase.student_name
                 %span.gh-purchase-row-group--mobile
                   = render 'layouts/group_chip', story_group: purchase.story_group
@@ -49,11 +48,7 @@
                 = render 'layouts/currency_token', story_group: purchase.story_group, size: 16
               %span.gh-purchase-row-time= purchase.time
     - else
-      %p.gh-small.mt-4
-        - if @dashboard.filter
-          W tej grupie nie ma jeszcze żadnych zakupów.
-        - else
-          Nikt jeszcze niczego nie kupił. Zakupy pojawią się tutaj same.
+      %p.gh-small.mt-4= @dashboard.filter ? t('.no_group_purchases') : t('.no_purchases')
 
   .gh-dashboard-side-column
     - if @dashboard.pending
@@ -61,18 +56,18 @@
       %section.gh-card.gh-todo-card
         .gh-card-frame
           .gh-card-inset
-            %p.gh-page-kicker Czeka na ocenę
+            %p.gh-page-kicker= t('.pending')
             %h2.gh-todo-card-title= pending.activity_group.name
             = render 'layouts/group_chip', story_group: pending.story_group
             %p.gh-small
-              = "Zostało #{pending.categories_count} #{gh_plural(pending.categories_count, 'kategoria', 'kategorie', 'kategorii')}"
-              = "dla #{pending.students_count} #{gh_plural(pending.students_count, 'studenta', 'studentów', 'studentów')}."
-            = link_to 'Oceń',
+              = t('.pending_left', categories: t('.pending_categories', count: pending.categories_count),
+                                   students:   t('.pending_students', count: pending.students_count))
+            = link_to t('.grade'),
               edit_story_group_activity_group_students_activity_group_categories_path(pending.story_group, pending.activity_group),
               class: 'gh-btn'
 
     %section.gh-panel.gh-my-groups-panel
-      %h2.gh-h2 Twoje grupy
+      %h2.gh-h2= t('.your_groups')
       - if groups.any?
         %ul.gh-my-groups-list
           - groups.each do |group|
@@ -81,14 +76,13 @@
                 = render 'layouts/group_thumb', story_group: group.story_group, size: :lg
                 %span
                   %b= group.story_group.name
-                  %small
-                    = "#{group.role}, #{group.students_count} #{gh_plural(group.students_count, 'student', 'studentów', 'studentów')}"
+                  %small= t('.group_meta', role: group.role, students: t('.students', count: group.students_count))
                 - if group.new_purchases.positive?
                   %span.gh-my-groups-list-item-alert
-                    = "#{group.new_purchases} #{gh_plural(group.new_purchases, 'nowy zakup', 'nowe zakupy', 'nowych zakupów')}"
+                    = t('.new_purchases', count: group.new_purchases)
       - else
-        %p.gh-small Nie prowadzisz jeszcze żadnej grupy.
+        %p.gh-small= t('.no_groups')
 
       = link_to new_story_group_path, class: 'gh-btn gh-btn--secondary' do
         %i.fa-solid.fa-plus
-        Utwórz grupę
+        = t('.create_group')
diff --git a/app/views/home/index.html.haml b/app/views/home/index.html.haml
index fa4939ec..85a4f7a8 100644
--- a/app/views/home/index.html.haml
+++ b/app/views/home/index.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, 'Start'
+- content_for :title, t('.title')
 
 = render @dashboard
diff --git a/app/views/invitation_mailer/invitation_email.html.haml b/app/views/invitation_mailer/invitation_email.html.haml
index 822985ed..b23e11ec 100644
--- a/app/views/invitation_mailer/invitation_email.html.haml
+++ b/app/views/invitation_mailer/invitation_email.html.haml
@@ -1,3 +1,3 @@
 = render 'shared/invitation_email',
-  lead:       "Zostałeś dodany jako #{@role_label} organizacji #{@organization_name} w Gamification Hub.",
+  lead:       t('.lead', role: @role_label, organization: @organization_name),
   token_link: @token_link
diff --git a/app/views/invitation_mailer/invitation_email.text.haml b/app/views/invitation_mailer/invitation_email.text.haml
index 822985ed..b23e11ec 100644
--- a/app/views/invitation_mailer/invitation_email.text.haml
+++ b/app/views/invitation_mailer/invitation_email.text.haml
@@ -1,3 +1,3 @@
 = render 'shared/invitation_email',
-  lead:       "Zostałeś dodany jako #{@role_label} organizacji #{@organization_name} w Gamification Hub.",
+  lead:       t('.lead', role: @role_label, organization: @organization_name),
   token_link: @token_link
diff --git a/app/views/items/_card.html.haml b/app/views/items/_card.html.haml
index 9819a7e0..a360df4b 100644
--- a/app/views/items/_card.html.haml
+++ b/app/views/items/_card.html.haml
@@ -34,7 +34,7 @@
           = offer.discount_label
         %span.gh-tag.gh-tag--no-lives{ hidden: !offer.zero_lives?, data: targets[:tag_life] }
           %i.fa-solid.fa-heart{ 'aria-hidden': 'true' }
-          Działa przy 0 życiach
+          = t('.zero_lives')
 
       %p.gh-rule-text{ class: ('gh-placeholder-text' if item.didactic_description.blank?), data: targets[:rules] }
         = item_rules(item)
@@ -49,12 +49,12 @@
               = buy
             - else
               %button.gh-btn{ type: 'button', tabindex: -1 }
-                %span{ data: targets[:buy_label] }= "Kup za #{price}"
+                %span{ data: targets[:buy_label] }= t('.buy', price: price)
 
         - if all_feet || state == :save
           .gh-requirement-block{ hidden: hide.call(:save), data: targets[:foot_save] }
             .gh-requirement-title
-              Zbierz jeszcze
+              = t('.collect_more')
               %b{ data: targets[:need] }= need
             .gh-progress-bar.gh-octagon-clip
               %i.gh-octagon-clip{ style: "--gh-p: #{(progress.clamp(0, 1) * 100).round}%", data: targets[:bar] }
@@ -73,5 +73,5 @@
                        'aria-valuemin': 0,
                        'aria-valuemax': rp.target,
                        'aria-valuenow': rp.collected,
-                       'aria-label': "Postęp do rangi #{rp.rank_name}" }
+                       'aria-label': t('.progress_label', rank: rp.rank_name) }
                 %i.gh-octagon-clip{ style: "--gh-p: #{gh_percent(rp.collected, rp.target)}%" }
diff --git a/app/views/items/_confirm_destroy.html.haml b/app/views/items/_confirm_destroy.html.haml
index fee14152..32f7d23a 100644
--- a/app/views/items/_confirm_destroy.html.haml
+++ b/app/views/items/_confirm_destroy.html.haml
@@ -1,22 +1,18 @@
-%h2#gh-del-title.gh-h2= "Usunąć „#{item.name}” ze sklepu?"
-%p
-  Przedmiot zniknie ze sklepu i z list. Studenci, którzy go kupili, zachowają
-  go, a w historii zostanie oznaczony jako „Usunięty z oferty”.
+%h2#gh-del-title.gh-h2= t('.title', name: item.name)
+%p= t('.body')
 
 - if bought.positive?
   %p.gh-warning-note{ role: 'alert' }
     %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-    %span
-      = "#{bought} #{gh_plural(bought, 'student ma', 'studentów ma', 'studentów ma')} ten przedmiot"
-      i zachowa go po usunięciu.
+    %span= t('.owners', count: bought)
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', edit_story_group_item_path(@story_group, item), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), edit_story_group_item_path(@story_group, item), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń z oferty', story_group_item_path(@story_group, item),
+  = button_to t('.remove'), story_group_item_path(@story_group, item),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/items/_form.html.haml b/app/views/items/_form.html.haml
index 6ef08f40..359f13d7 100644
--- a/app/views/items/_form.html.haml
+++ b/app/views/items/_form.html.haml
@@ -7,12 +7,11 @@
 
 %section.gh-panel.gh-page-header.gh-page-header--stacked
   %p.gh-breadcrumbs
-    = link_to 'Przedmioty', story_group_items_path(@story_group)
+    = link_to t('.breadcrumb'), story_group_items_path(@story_group)
     %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
-    %span= editing ? (item.name_was.presence || item.name) : 'Nowy przedmiot'
-  %h1.gh-h1= editing ? 'Edytuj przedmiot' : 'Nowy przedmiot'
-  %p.gh-lead
-    = editing ? 'Podgląd obok pokazuje kartę po zmianach.' : 'Wypełnij kartę, a podgląd obok pokaże, jak zobaczą ją studenci.'
+    %span= editing ? (item.name_was.presence || item.name) : t('.new_title')
+  %h1.gh-h1= editing ? t('.edit_title') : t('.new_title')
+  %p.gh-lead= editing ? t('.edit_lead') : t('.new_lead')
 
 - form_data = { controller: 'item-form',
                 action:     'gh:image-crop->item-form#art',
@@ -21,7 +20,8 @@
                 item_form_badge_discount_value:  card.badges_discount,
                 item_form_badge_names_value:     card.discount_badges.map(&:name).to_json,
                 item_form_example_rank_order_value:  example.rank_order.to_json,
-                item_form_example_badge_order_value: example.badge_order.to_json, }
+                item_form_example_badge_order_value: example.badge_order.to_json,
+                item_form_i18n_value:                item_form_wording.to_json, }
 
 = form_with model: [@story_group, item], data: form_data do |f|
 
@@ -31,19 +31,18 @@
         %p.gh-info-banner
           %i.fa-solid.fa-users{ 'aria-hidden': 'true' }
           %span
-            %b
-              = "#{bought} #{gh_plural(bought, 'student ma', 'studentów ma', 'studentów ma')} ten przedmiot."
-            Zmiany ceny, wymagań i zniżek dotyczą tylko nowych zakupów.
+            %b= t('.owners', count: bought)
+            = t('.owners_note')
 
       .gh-form-section
-        %h2.gh-h3 Karta przedmiotu
-        %p.gh-field-hint Tak przedmiot wygląda w sklepie i w ekwipunku studenta.
+        %h2.gh-h3= t('.card')
+        %p.gh-field-hint= t('.card_hint')
 
         .gh-form-field
-          = f.label :name, 'Nazwa'
+          = f.label :name, t('shared.actions.name')
           .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:name)) }
             = f.text_field :name, maxlength: 50, autocomplete: 'off',
-              placeholder: 'np. Poprawa wejściówki',
+              placeholder: t('.name_placeholder'),
               'aria-invalid': (error.call(:name) ? 'true' : nil),
               'aria-describedby': (error.call(:name) ? 'gh-item-name-error' : nil),
               data: { item_form_target: 'name', action: 'item-form#refresh' }
@@ -53,10 +52,10 @@
               %span= error.call(:name)
 
         .gh-form-field
-          = f.label :didactic_description, 'Co daje studentowi'
+          = f.label :didactic_description, t('.rules')
           .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:didactic_description)) }
             = f.text_area :didactic_description, rows: 2, maxlength: 255,
-              placeholder: 'np. Możliwość ponownego napisania wejściówki',
+              placeholder: t('.rules_placeholder'),
               'aria-invalid': (error.call(:didactic_description) ? 'true' : nil),
               'aria-describedby': (error.call(:didactic_description) ? 'gh-item-rules-error' : nil),
               data: { item_form_target: 'rules', action: 'item-form#refresh' }
@@ -64,15 +63,15 @@
             %p#gh-item-rules-error.gh-field-error{ role: 'alert' }
               %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
               %span= error.call(:didactic_description)
-          %span.gh-field-hint Opis dydaktyczny: konkretna korzyść, bez fabuły.
+          %span.gh-field-hint= t('.rules_hint')
 
         .gh-form-field
           = f.label :story_description do
-            Opis fabularny
-            %small (opcjonalnie)
+            = t('.story')
+            %small= t('shared.actions.optional')
           .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:story_description)) }
             = f.text_area :story_description, rows: 2, maxlength: 255,
-              placeholder: 'np. Awaryjny powrót statku do bazy',
+              placeholder: t('.story_placeholder'),
               'aria-invalid': (error.call(:story_description) ? 'true' : nil),
               'aria-describedby': (error.call(:story_description) ? 'gh-item-story-error' : nil),
               data: { item_form_target: 'story', action: 'item-form#refresh' }
@@ -86,10 +85,10 @@
           refresh_action: 'item-form#refresh'
 
       .gh-form-section
-        %h2.gh-h3 Cena
+        %h2.gh-h3= t('.price_section')
 
         .gh-form-field
-          = f.label :price, 'Cena'
+          = f.label :price, t('.price')
           .gh-price-field-row
             .gh-text-input.gh-text-input--numeric{ class: ('gh-text-input--invalid' if error.call(:price)) }
               = f.number_field :price, min: 1, step: 1,
@@ -109,57 +108,53 @@
             'aria-labelledby': 'gh-item-zero-label',
             data: { item_form_target: 'zero', action: 'change->item-form#refresh' }
           %span
-            %b#gh-item-zero-label Można kupić przy 0 życiach
-            %span.gh-field-hint Przydaje się dla przedmiotów, które przywracają życie.
+            %b#gh-item-zero-label= t('.zero_lives')
+            %span.gh-field-hint= t('.zero_lives_hint')
 
       .gh-form-section
-        %h2.gh-h3 Kto może kupić
-        %p.gh-field-hint Bez wymagań przedmiot jest dostępny dla wszystkich.
+        %h2.gh-h3= t('.who_section')
+        %p.gh-field-hint= t('.who_hint')
 
         .gh-sentence-row
-          %span Kupić może
+          %span= t('.who')
           %span.gh-select-input
             = f.select :unlock_rank_id, item_unlock_rank_options(shelf.ranks, item.unlock_rank_id), {},
-              'aria-label': 'Kto może kupić',
+              'aria-label': t('.who_label'),
               data: { item_form_target: 'unlockRank', action: 'item-form#refresh' }
             %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
         .gh-sentence-row
-          %span Wymagane odznaki
+          %span= t('.required_badges')
           - if badges.any?
             = render 'badge_chips', f: f, field: :unlock_badge_ids, badges: badges,
-              legend: 'Wymagane odznaki', placeholder: 'Dodaj odznakę…',
+              legend: t('.required_badges'), placeholder: t('.add_badge'),
               form_target: 'unlockBadge'
           - else
-            %span.gh-field-hint W tej grupie nie ma jeszcze odznak.
+            %span.gh-field-hint= t('.no_badges')
 
         %p.gh-explainer-note{ data: { item_form_target: 'unlockText' } }= item_unlock_sentence(item)
 
       .gh-form-section
-        %h2.gh-h3 Zniżki
-        %p.gh-field-hint
-          Zniżka z rangi to procent przypisany do rangi studenta. Zniżki z odznak
-          się sumują. Wystarczy spełnić jeden z warunków, żeby zniżka zadziałała
-          — bez warunków dostaje ją każdy kupujący. Wysokość liczy się zawsze
-          z rangi i wszystkich odznak studenta, także tych niewybranych tutaj.
+        %h2.gh-h3= t('.discounts_section')
+        %p.gh-field-hint= t('.discounts_hint')
 
         .gh-sentence-row
-          %span Zniżka dla rang
+          %span= t('.rank_discount')
           %span.gh-select-input
             = f.select :min_rank_for_discount_id,
               item_discount_rank_options(shelf.ranks, item.min_rank_for_discount_id), {},
-              'aria-label': 'Zniżka dla rang',
+              'aria-label': t('.rank_discount'),
               data: { item_form_target: 'discountRank', action: 'item-form#refresh' }
             %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
         .gh-sentence-row
-          %span Zniżka za odznaki
+          %span= t('.badge_discount')
           - if badges.any?
             = render 'badge_chips', f: f, field: :discount_badge_ids, badges: badges,
-              legend: 'Odznaki ze zniżką', placeholder: 'Dodaj odznakę ze zniżką…',
+              legend: t('.discount_badges'), placeholder: t('.add_discount_badge'),
               form_target: 'discountBadge', show_discount: true
           - else
-            %span.gh-field-hint W tej grupie nie ma jeszcze odznak.
+            %span.gh-field-hint= t('.no_badges')
 
         .gh-explainer-note
           %p{ data: { item_form_target: 'discountText' } }= item_discount_sentence(item, card, example)
@@ -173,26 +168,24 @@
 
       - if editing
         .gh-form-section
-          %h2.gh-h3 Usuwanie
-          %p.gh-field-hint
-            Przedmiot zniknie ze sklepu i z list. Studenci, którzy go kupili,
-            nadal go mają, a w ich historii zostanie jako „Usunięty z oferty”.
+          %h2.gh-h3= t('shared.actions.removal')
+          %p.gh-field-hint= t('.removal_hint')
           .gh-button-row
             = link_to confirm_destroy_story_group_item_path(@story_group, item),
               class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
               %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-              Usuń przedmiot
+              = t('.remove')
 
-    %aside.gh-preview-column{ 'aria-label': 'Podgląd' }
+    %aside.gh-preview-column{ 'aria-label': t('shared.actions.preview') }
       = render 'preview', item: item, card: card
 
   %template{ data: { item_form_target: 'reqRank' } }
     %li
-      Wymaga rangi
+      = t('items.labels.requires_rank')
       %b
   %template{ data: { item_form_target: 'reqBadge' } }
     %li
-      Wymaga odznaki
+      = t('items.labels.requires_badge')
       %b
   %template{ data: { item_form_target: 'warnTemplate' } }
     %p.gh-warning-note--alt
@@ -200,9 +193,9 @@
       %span
 
   .gh-panel.gh-form-actions-bar
-    = link_to 'Anuluj', story_group_items_path(@story_group), class: 'gh-link-button'
+    = link_to t('shared.actions.cancel'), story_group_items_path(@story_group), class: 'gh-link-button'
     %span.gh-form-actions-spacer
     %button.gh-btn{ type: 'submit' }
       - unless editing
         %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      = editing ? 'Zapisz zmiany' : 'Dodaj przedmiot'
+      = editing ? t('shared.actions.save_changes') : t('.create')
diff --git a/app/views/items/_grid_card.html.haml b/app/views/items/_grid_card.html.haml
index f634b195..940aec9c 100644
--- a/app/views/items/_grid_card.html.haml
+++ b/app/views/items/_grid_card.html.haml
@@ -16,11 +16,11 @@
               %i.fa-solid.fa-lock{ 'aria-hidden': 'true' }
               = label
           - if card.discounts?
-            %span.gh-tag.gh-tag--discount Zniżka
+            %span.gh-tag.gh-tag--discount= t('.discount')
           - if card.zero_lives?
             %span.gh-tag.gh-tag--no-lives
               %i.fa-solid.fa-heart{ 'aria-hidden': 'true' }
-              Przy 0 życiach
+              = t('.zero_lives')
 
       %p.gh-rule-text= item.didactic_description
       - if item.story_description.present?
@@ -30,5 +30,5 @@
         %span.gh-card-meta= item_bought_line(bought)
         .gh-card-actions
           = link_to edit_story_group_item_path(@story_group, item),
-            class: 'gh-icon-button', 'aria-label': "Edytuj przedmiot #{item.name}" do
+            class: 'gh-icon-button', 'aria-label': t('.edit_label', name: item.name) do
             %i.fa-solid.fa-pen{ 'aria-hidden': 'true' }
diff --git a/app/views/items/_preview.html.haml b/app/views/items/_preview.html.haml
index 5df08c5b..f27b4f71 100644
--- a/app/views/items/_preview.html.haml
+++ b/app/views/items/_preview.html.haml
@@ -21,36 +21,36 @@
 
 %details.gh-preview-details{ open: true }
   %summary
-    Podgląd karty
+    = t('.summary')
     %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
   %section.gh-panel.gh-preview-panel
-    %h3 Tak zobaczą to studenci
+    %h3= t('.students_view')
 
-    .gh-segmented-toggle-2.gh-octagon-clip{ role: 'group', 'aria-label': 'Stan karty' }
+    .gh-segmented-toggle-2.gh-octagon-clip{ role: 'group', 'aria-label': t('.state') }
       %button{ type: 'button', 'aria-pressed': 'true', value: 'afford',
                data: { action: 'item-form#state', item_form_target: 'state' } }
-        Dostępny
+        = t('.afford')
       %button{ type: 'button', 'aria-pressed': 'false', value: 'save',
                data: { action: 'item-form#state', item_form_target: 'state' } }
-        Zbierasz
+        = t('.save')
       %button{ type: 'button', 'aria-pressed': 'false', value: 'sealed',
                disabled: !card.requires?,
                data: { action: 'item-form#state', item_form_target: 'state' } }
-        Zapieczętowany
+        = t('.sealed')
 
     %span.gh-field-hint{ hidden: card.requires?, data: { item_form_target: 'sealHint' } }
-      Bez wymagań przedmiot nigdy nie będzie zapieczętowany.
+      = t('.seal_hint')
 
     .gh-item-preview-card
       = render 'card', item: item, card: card, state: :afford,
         need: need, progress: 0.6, targets: targets, all_feet: true
 
   %section.gh-panel.gh-preview-panel
-    %h3 Miniatura w powiadomieniach
+    %h3= t('.thumb')
     .gh-preview-thumb-row
       = render 'layouts/item_thumb', item: item,
         inner_data: { item_form_target: 'thumbArt' }
       %span
         %b{ data: { item_form_target: 'thumbName' } }= item_name(item)
-        %span.gh-small Zakup studenta, dziś 10:21
+        %span.gh-small= t('.thumb_sample')
diff --git a/app/views/items/confirm_destroy.html.haml b/app/views/items/confirm_destroy.html.haml
index 372f916c..94c28587 100644
--- a/app/views/items/confirm_destroy.html.haml
+++ b/app/views/items/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń przedmiot #{@item.name}"
+- content_for :title, t('.page_title', name: @item.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/items/edit.html.haml b/app/views/items/edit.html.haml
index 65871598..9643cc11 100644
--- a/app/views/items/edit.html.haml
+++ b/app/views/items/edit.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, "Edytuj przedmiot - #{@item.name}"
+- content_for :title, t('.page_title', name: @item.name)
 
 = render 'form', item: @item, shelf: @shelf
diff --git a/app/views/items/index.html.haml b/app/views/items/index.html.haml
index ca458ea8..1743a1cc 100644
--- a/app/views/items/index.html.haml
+++ b/app/views/items/index.html.haml
@@ -1,16 +1,14 @@
-- content_for :title, 'Przedmioty'
+- content_for :title, t('.title')
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Przedmioty
-    %p.gh-lead
-      = "#{@shelf.size} #{gh_plural(@shelf.size, 'przedmiot', 'przedmioty', 'przedmiotów')} w sklepie,"
-      od najtańszego.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead', count: @shelf.size)
 
   .gh-button-row
     = link_to new_story_group_item_path(@story_group), class: 'gh-btn' do
       %i.fa-solid.fa-plus
-      Nowy przedmiot
+      = t('.new')
 
 - if @shelf.any?
   .gh-badge-grid--teacher
@@ -18,7 +16,5 @@
       = render 'grid_card', item: slot.item, card: @shelf.card_for(slot.item), bought: slot.bought
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Sklep jest jeszcze pusty
-    %p.gh-lead
-      Dodaj przedmioty, żeby zebrana waluta miała na co iść. Każdy może mieć
-      wymagania i zniżki, więc sklep otwiera się stopniowo wraz z postępami.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/items/new.html.haml b/app/views/items/new.html.haml
index 48413ad2..e439c97d 100644
--- a/app/views/items/new.html.haml
+++ b/app/views/items/new.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, 'Nowy przedmiot'
+- content_for :title, t('.page_title')
 
 = render 'form', item: @item, shelf: @shelf
diff --git a/app/views/join/_cancel.html.haml b/app/views/join/_cancel.html.haml
index 0b46a3f1..b9e318c3 100644
--- a/app/views/join/_cancel.html.haml
+++ b/app/views/join/_cancel.html.haml
@@ -1,4 +1,4 @@
 - if @in_modal
-  %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+  %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
 - else
-  = link_to 'Anuluj', home_path, class: 'gh-btn gh-btn--secondary'
+  = link_to t('shared.actions.cancel'), home_path, class: 'gh-btn gh-btn--secondary'
diff --git a/app/views/join/_step_code.html.haml b/app/views/join/_step_code.html.haml
index 66147941..b7444d38 100644
--- a/app/views/join/_step_code.html.haml
+++ b/app/views/join/_step_code.html.haml
@@ -1,9 +1,9 @@
 - error = local_assigns[:lookup]&.error
 - member_of = local_assigns[:lookup]&.member_of
 
-%p.gh-small.mb-1 Krok 1 z 2
-%h2.gh-h2#gh-join-title Dołącz do grupy
-%p Wpisz 6-znakowy kod, który podał prowadzący.
+%p.gh-small.mb-1= t('.step')
+%h2.gh-h2#gh-join-title= t('.title')
+%p= t('.hint')
 
 = form_with url:    lookup_join_index_path,
             method: :get,
@@ -11,7 +11,7 @@
                       turbo_frame: (@in_modal ? 'modal' : nil), } do
   = hidden_field_tag :code, code, data: { join_code_target: 'code' }
 
-  .gh-join-code-inputs{ role: 'group', 'aria-label': 'Kod zaproszenia' }
+  .gh-join-code-inputs{ role: 'group', 'aria-label': t('.code_label') }
     - StoryGroupInvite::CODE_LENGTH.times do |index|
       %span.gh-join-code-slot
         %input{type:           'text',
@@ -21,7 +21,7 @@
                spellcheck:     'false',
                value:          code.to_s[index],
                autofocus:      index.zero?,
-               'aria-label':   "Znak #{index + 1} z #{StoryGroupInvite::CODE_LENGTH}",
+               'aria-label':   t('.slot_label', index: index + 1, total: StoryGroupInvite::CODE_LENGTH),
                data:           { join_code_target: 'slot',
                                  action:           'input->join-code#type keydown->join-code#key paste->join-code#paste', },}
 
@@ -29,8 +29,8 @@
     %p.gh-field-error.pb-2{ role: 'alert' }
       %i.fa-solid.fa-triangle-exclamation.fa-fw.gh-join-icon{ 'aria-hidden': 'true' }
       %span
-        Już należysz do tej grupy.
-        = link_to 'Otwórz grupę',
+        = t('.member')
+        = link_to t('.open_group'),
                   story_group_path(member_of),
                   class: 'gh-link-button',
                   data:  { turbo_frame: '_top' }
@@ -41,8 +41,8 @@
 
   %p.gh-small.gh-join-hint
     %i.fa-solid.fa-camera.fa-fw.gh-join-icon{ 'aria-hidden': 'true' }
-    Masz kod QR? Zeskanuj go aparatem telefonu, a kod wpisze się sam.
+    = t('.qr_hint')
 
   .gh-dialog-button-row
     = render 'join/cancel'
-    %button.gh-btn{ type: 'submit', data: { join_code_target: 'submit' } } Dalej
+    %button.gh-btn{ type: 'submit', data: { join_code_target: 'submit' } }= t('shared.actions.next')
diff --git a/app/views/join/_step_done.html.haml b/app/views/join/_step_done.html.haml
index e69a9b56..15cd902b 100644
--- a/app/views/join/_step_done.html.haml
+++ b/app/views/join/_step_done.html.haml
@@ -1,14 +1,12 @@
 %span.gh-card-art.gh-joined-group-art{ 'aria-hidden': 'true' }
   = gh_group_cover(story_group) || gh_monogram(story_group.name)
 
-%h2#gh-join-title.gh-h2= "Dołączono do grupy #{story_group.name}"
+%h2#gh-join-title.gh-h2= t('.title', name: story_group.name)
 %p
-  = "Prowadzi #{story_group.owner.full_name}."
-  = succeed '.' do
-    Jesteś tam jako
-    %b= membership.display_name
-  = "Walutą w tej grupie są #{story_group.currency_name}."
+  = t('.led_by', name: story_group.owner.full_name)
+  = t('.you_are_html', name: tag.b(membership.display_name))
+  = t('.currency', currency: story_group.currency_name)
 
 .gh-dialog-button-row
-  = link_to 'Gotowe', story_group_path(story_group), class: 'gh-btn',
+  = link_to t('.done'), story_group_path(story_group), class: 'gh-btn',
     data: { turbo_frame: '_top' }
diff --git a/app/views/join/_step_nickname.html.haml b/app/views/join/_step_nickname.html.haml
index 1e7c12df..8783aefa 100644
--- a/app/views/join/_step_nickname.html.haml
+++ b/app/views/join/_step_nickname.html.haml
@@ -1,10 +1,8 @@
 - nickname_error = local_assigns[:result]&.nickname_error
 
-%p.gh-small.mb-1 Krok 2 z 2
-%h2.gh-h2#gh-join-title= "Dołączasz do grupy #{story_group.name}"
-%p
-  W tej grupie inni zobaczą Cię pod pseudonimem — także w rankingu.
-  Możesz go później zmienić w ustawieniach w grupie.
+%p.gh-small.mb-1= t('.step')
+%h2.gh-h2#gh-join-title= t('.title', name: story_group.name)
+%p= t('.hint')
 
 = form_with url:    join_index_path,
             method: :post,
@@ -12,7 +10,7 @@
   = hidden_field_tag :code, code
 
   .gh-form-field
-    = label_tag :nickname, 'Pseudonim w tej grupie'
+    = label_tag :nickname, t('.nickname')
     .gh-text-input{ class: ('gh-text-input--invalid' if nickname_error) }
       = text_field_tag :nickname, params[:nickname],
                        maxlength:          24,
@@ -27,11 +25,9 @@
         %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
         %span= nickname_error
     - else
-      %span.gh-field-hint#gh-nick-note
-        Zostaw puste, jeśli chcesz używać imienia i nazwiska.
-        Pseudonim możesz ustawić później.
+      %span.gh-field-hint#gh-nick-note= t('.nickname_hint')
     -# haml-lint:enable RepeatedId
 
   .gh-dialog-button-row
     = render 'join/cancel'
-    %button.gh-btn{ type: 'submit' } Dołącz do grupy
+    %button.gh-btn{ type: 'submit' }= t('.join')
diff --git a/app/views/join/create.html.haml b/app/views/join/create.html.haml
index bacca5c6..4473eaa3 100644
--- a/app/views/join/create.html.haml
+++ b/app/views/join/create.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Dołączono do grupy'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/join/new.html.haml b/app/views/join/new.html.haml
index 83337bfe..4ccfc3c4 100644
--- a/app/views/join/new.html.haml
+++ b/app/views/join/new.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Dołącz do grupy'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/join/show.html.haml b/app/views/join/show.html.haml
index b212209f..a684f32a 100644
--- a/app/views/join/show.html.haml
+++ b/app/views/join/show.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Dołącz do grupy'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/layouts/_account_menu.html.haml b/app/views/layouts/_account_menu.html.haml
index a3519de2..3dd1e843 100644
--- a/app/views/layouts/_account_menu.html.haml
+++ b/app/views/layouts/_account_menu.html.haml
@@ -1,5 +1,5 @@
 %dialog#gh-account-menu.gh-dialog.gh-dialog--menu.gh-dialog--anchored{ data: { action: 'click->menu#closeOnBackdrop' },
-                                                                       'aria-label': 'Konto' }
+                                                                       'aria-label': t('.label') }
   .gh-dialog-body.gh-octagon-clip
     %span.gh-sheet-drag-handle{ 'aria-hidden': 'true' }
 
@@ -14,14 +14,16 @@
       %li
         %button{ type: 'button' }
           %i.fa-solid.fa-gear
-          %span Ustawienia konta
+          %span= t('.account_settings')
       %li
         %button{ type: 'button', data: { action: 'theme#toggle' } }
           %i.fa-solid.fa-moon.gh-theme-icon-moon
           %i.fa-solid.fa-sun.gh-theme-icon-sun
           %span{ data: { theme_target: 'label' } }
-            = gh_theme == 'dark' ? 'Jasny motyw' : 'Ciemny motyw'
+            = gh_theme == 'dark' ? t('layouts.theme.light') : t('layouts.theme.dark')
+      %li
+        = render 'layouts/locale_switcher', menu: true
       %li
         = link_to logout_path, data: { turbo_method: :delete } do
           %i.fa-solid.fa-arrow-right-from-bracket
-          %span Wyloguj się
+          %span= t('.logout')
diff --git a/app/views/layouts/_deck.html.haml b/app/views/layouts/_deck.html.haml
index db4513b2..6ff9de4f 100644
--- a/app/views/layouts/_deck.html.haml
+++ b/app/views/layouts/_deck.html.haml
@@ -1,6 +1,6 @@
 - story_group = chrome.story_group
 
-%section.gh-current-group-card{ 'aria-label': "Grupa #{chrome.name}" }
+%section.gh-current-group-card{ 'aria-label': t('.group', name: chrome.name) }
   .gh-current-group-card-frame.gh-octagon-clip
     .gh-current-group-card-inner.gh-octagon-clip
       - cover = gh_group_cover(story_group)
@@ -12,13 +12,13 @@
         %p.gh-current-group-card-role= chrome.role_label
 
       %button.gh-link-button.gh-current-group-card-switch-trigger{ type: 'button',
-                                     title: 'Zmień grupę',
+                                     title: t('.switch'),
                                      data: { action: 'menu#open',
                                              menu_id_param: 'gh-group-switcher' } }
         %i.fa-solid.fa-right-left{ 'aria-hidden': 'true' }
-        %span Zmień grupę
+        %span= t('.switch')
 
-      %nav.gh-sidebar-nav{ 'aria-label': 'Sekcje grupy' }
+      %nav.gh-sidebar-nav{ 'aria-label': t('.sections') }
         - chrome.items.each do |item|
           - on = item.current?(current_path)
           = link_to item.path, class: "gh-sidebar-link #{'gh-sidebar-link--active' if on}",
diff --git a/app/views/layouts/_flash.html.haml b/app/views/layouts/_flash.html.haml
index 41b8df1d..074bc251 100644
--- a/app/views/layouts/_flash.html.haml
+++ b/app/views/layouts/_flash.html.haml
@@ -9,5 +9,5 @@
       %button{ class: 'gh-close absolute right-1 top-1/2 -translate-y-1/2',
                type: 'button',
                data: { action: 'flash#dismiss' },
-               'aria-label': 'Zamknij' }
+               'aria-label': t('shared.actions.close') }
         %i.fa-solid.fa-xmark
diff --git a/app/views/layouts/_group_switcher.html.haml b/app/views/layouts/_group_switcher.html.haml
index 628237b2..c77dd40c 100644
--- a/app/views/layouts/_group_switcher.html.haml
+++ b/app/views/layouts/_group_switcher.html.haml
@@ -6,7 +6,7 @@
   .gh-dialog-body.gh-octagon-clip
     %span.gh-sheet-drag-handle{ 'aria-hidden': 'true' }
     .gh-popover-header
-      %h2#gh-switch-title.gh-h3 Zmień grupę
+      %h2#gh-switch-title.gh-h3= t('.title')
 
     %ul.gh-menu-list
       - groups.each do |story_group|
@@ -16,10 +16,10 @@
             = render 'layouts/group_thumb', story_group: story_group, size: nil
             %span= story_group.name
             - if here
-              %span.gh-current-badge Tu jesteś
+              %span.gh-current-badge= t('.here')
 
     .gh-popover-footer
       = link_to new_join_path, class: 'gh-btn gh-btn--secondary',
         data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-plus
-        Dołącz do grupy
+        = t('.join')
diff --git a/app/views/layouts/_locale_switcher.html.haml b/app/views/layouts/_locale_switcher.html.haml
new file mode 100644
index 00000000..1348de1e
--- /dev/null
+++ b/app/views/layouts/_locale_switcher.html.haml
@@ -0,0 +1,8 @@
+- other_locale = (I18n.available_locales - [I18n.locale]).first
+- menu = local_assigns.fetch(:menu, false)
+
+= button_to locale_path, method: :patch, params: { locale: other_locale },
+  class: (menu ? nil : 'gh-link-button'), lang: other_locale, 'aria-label': t('.label') do
+  - if menu
+    %i.fa-solid.fa-language{ 'aria-hidden': 'true' }
+  %span= t('.switch_to')
diff --git a/app/views/layouts/_more_sheet.html.haml b/app/views/layouts/_more_sheet.html.haml
index e5a4e2bc..a5c26eda 100644
--- a/app/views/layouts/_more_sheet.html.haml
+++ b/app/views/layouts/_more_sheet.html.haml
@@ -2,7 +2,7 @@
                                                  'aria-labelledby': 'gh-more-title' }
   .gh-dialog-body.gh-octagon-clip
     %span.gh-sheet-drag-handle{ 'aria-hidden': 'true' }
-    %h2#gh-more-title.gh-h2 Więcej
+    %h2#gh-more-title.gh-h2= t('shared.actions.more')
 
     - if chrome
       %ul.gh-menu-list.gh-menu-list--nav
@@ -16,24 +16,24 @@
         %li
           = link_to new_story_group_path do
             %i.fa-solid.fa-plus
-            %span Utwórz grupę
+            %span= t('.create_group')
 
-    %p.gh-popover-section-label Konto
+    %p.gh-popover-section-label= t('.account')
     %ul.gh-menu-list
       %li
         %button{ type: 'button' }
           %i.fa-solid.fa-gear
-          %span Ustawienia konta
+          %span= t('.account_settings')
       %li
         %button{ type: 'button', data: { action: 'theme#toggle' } }
           %i.fa-solid.fa-moon.gh-theme-icon-moon
           %i.fa-solid.fa-sun.gh-theme-icon-sun
           %span{ data: { theme_target: 'label' } }
-            = gh_theme == 'dark' ? 'Jasny motyw' : 'Ciemny motyw'
+            = gh_theme == 'dark' ? t('layouts.theme.light') : t('layouts.theme.dark')
       %li
         = link_to logout_path, data: { turbo_method: :delete } do
           %i.fa-solid.fa-arrow-right-from-bracket
-          %span Wyloguj się
+          %span= t('.logout')
 
     .gh-button-stack
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'menu#close' } } Zamknij
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'menu#close' } }= t('shared.actions.close')
diff --git a/app/views/layouts/_theme_toggle.html.haml b/app/views/layouts/_theme_toggle.html.haml
index f24023b2..8847f12e 100644
--- a/app/views/layouts/_theme_toggle.html.haml
+++ b/app/views/layouts/_theme_toggle.html.haml
@@ -1,10 +1,11 @@
 .gh-auth-footer.relative.z-10{ data: { controller: 'theme',
-                                theme_light_label_value: 'Jasny motyw',
-                                theme_dark_label_value: 'Ciemny motyw' } }
+                                theme_light_label_value: t('layouts.theme.light'),
+                                theme_dark_label_value: t('layouts.theme.dark') } }
   %button.gh-link-button{ type: 'button',
                       data: { action: 'theme#toggle', theme_target: 'label' },
-                      'aria-label': 'Przełącz motyw' }
-    = gh_theme == 'dark' ? 'Jasny motyw' : 'Ciemny motyw'
+                      'aria-label': t('layouts.theme.toggle') }
+    = gh_theme == 'dark' ? t('layouts.theme.light') : t('layouts.theme.dark')
+  = render 'layouts/locale_switcher'
   %span
-    Pomoc:
-    %button.gh-link-button{ type: 'button' } kontakt
+    = t('.help')
+    %button.gh-link-button{ type: 'button' }= t('.contact')
diff --git a/app/views/layouts/application.html.haml b/app/views/layouts/application.html.haml
index c234997d..dc019e8f 100644
--- a/app/views/layouts/application.html.haml
+++ b/app/views/layouts/application.html.haml
@@ -1,5 +1,5 @@
 !!!
-%html{ lang: 'pl', data: { gh_theme: gh_theme } }
+%html{ lang: I18n.locale, data: { gh_theme: gh_theme } }
   %head
     %meta{ charset: 'utf-8' }/
     %title= content_for(:title) || 'Gamification Hub'
@@ -29,9 +29,11 @@
           = yield
         = render 'layouts/theme_toggle'
     - else
-      .gh-app-shell{data: { controller:              'theme menu sidebar',
-                            theme_light_label_value: 'Jasny motyw',
-                            theme_dark_label_value:  'Ciemny motyw', }}
+      .gh-app-shell{data: { controller:                   'theme menu sidebar',
+                            theme_light_label_value:      t('layouts.theme.light'),
+                            theme_dark_label_value:       t('layouts.theme.dark'),
+                            sidebar_expand_label_value:   t('layouts.sidebar.expand'),
+                            sidebar_collapse_label_value: t('layouts.sidebar.collapse'), }}
         = render Shared::HeaderComponent.new(user:         @current_user,
                                              group_chrome: gh_group_chrome,)
 
diff --git a/app/views/layouts/mailer.html.haml b/app/views/layouts/mailer.html.haml
index 0ec6e9a4..4f8ee924 100644
--- a/app/views/layouts/mailer.html.haml
+++ b/app/views/layouts/mailer.html.haml
@@ -1,5 +1,5 @@
 !!!
-%html
+%html{ lang: I18n.locale }
   %head
     %meta{content: "text/html; charset=utf-8", "http-equiv" => "Content-Type"}/
     :css
diff --git a/app/views/notifications/_notification.html.haml b/app/views/notifications/_notification.html.haml
index 9e194ea1..17e931a2 100644
--- a/app/views/notifications/_notification.html.haml
+++ b/app/views/notifications/_notification.html.haml
@@ -8,7 +8,7 @@
     = render 'layouts/item_thumb', item: notification.item
     %span.gh-notification-row-text
       %b= student.full_name
-      %span= "Zakup: #{notification.item.name}"
-      %small= "#{story_group.name}, #{gh_when(notification.created_at)}"
+      %span= t('.purchase', name: notification.item.name)
+      %small= t('.meta', group: story_group.name, when: gh_when(notification.created_at))
     - if unread
-      %span.gh-notification-unread-dot.gh-octagon-clip{ 'aria-label': 'nowe' }
+      %span.gh-notification-unread-dot.gh-octagon-clip{ 'aria-label': t('.unread') }
diff --git a/app/views/notifications/_panel.html.haml b/app/views/notifications/_panel.html.haml
index 93ec495d..201c1948 100644
--- a/app/views/notifications/_panel.html.haml
+++ b/app/views/notifications/_panel.html.haml
@@ -1,19 +1,19 @@
 .gh-popover-header
-  %h2.gh-h3 Powiadomienia
+  %h2.gh-h3= t('.title')
   - if unread.any?
     = button_to mark_as_read_notifications_path, class: 'gh-link-button' do
       %i.fa-solid.fa-check-double
-      Oznacz wszystkie
+      = t('.mark_all')
 
 - if notifications.any?
   - if unread.any?
-    %p.gh-popover-section-label Nowe
+    %p.gh-popover-section-label= t('.new')
     %ul.gh-notification-list
       = render partial: 'notifications/notification', collection: unread, as: :notification
 
   - if read.any?
-    %p.gh-popover-section-label Wcześniej
+    %p.gh-popover-section-label= t('.earlier')
     %ul.gh-notification-list
       = render partial: 'notifications/notification', collection: read, as: :notification
 - else
-  %p.gh-small Brak powiadomień.
+  %p.gh-small= t('.empty')
diff --git a/app/views/organizations/_admin_form.html.haml b/app/views/organizations/_admin_form.html.haml
index c6a407fa..ab817c9f 100644
--- a/app/views/organizations/_admin_form.html.haml
+++ b/app/views/organizations/_admin_form.html.haml
@@ -1,17 +1,15 @@
 = form_with model: user, url: add_admin_organization_path(@organization),
   data: { turbo_frame: (@in_modal ? 'modal' : nil) } do |form|
-  %h2.gh-h2 Dodaj administratora
-  %p
-    Wyślemy zaproszenie na podany adres. Po pierwszym logowaniu administrator
-    uzupełni swoje dane.
+  %h2.gh-h2= t('.title')
+  %p= t('.hint')
 
-  = render 'organizations/field', form: form, record: user, attribute: :email, label: 'Adres e-mail',
+  = render 'organizations/field', form: form, record: user, attribute: :email, label: t('.email'),
                                   input: :email_field,
-                                  options: { placeholder: 'jan.nowak@example.com', autofocus: true }
+                                  options: { placeholder: t('.email_placeholder'), autofocus: true }
   - if (error = user.errors[:organization].first)
     %p.gh-field-error{ role: 'alert' }
       %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
       %span= error
 
   = render 'organizations/dialog_actions', cancel_path: organization_path(@organization),
-                                           submit_label: 'Wyślij zaproszenie'
+                                           submit_label: t('.submit')
diff --git a/app/views/organizations/_admins.html.haml b/app/views/organizations/_admins.html.haml
index 08da384c..e2c602f7 100644
--- a/app/views/organizations/_admins.html.haml
+++ b/app/views/organizations/_admins.html.haml
@@ -1,5 +1,5 @@
 %section.gh-panel.gh-organizations-panel
-  %h2.gh-h3.gh-organizations-panel-title Administratorzy
+  %h2.gh-h3.gh-organizations-panel-title= t('.title')
 
   - if admins.any?
     - admins.each do |admin|
@@ -7,9 +7,9 @@
       .gh-organization-member-row{ id: dom_id(admin, :admin) }
         = render 'organizations/person', user: admin
         %span.gh-teacher-role
-          Administrator
+          = t('.role')
           - if admin.first_login?
-            %small Zaproszenie wysłane
+            %small= t('.invited')
         - if manage_admins
           %span
           %span.gh-organization-member-actions
@@ -18,9 +18,9 @@
                                                                   name: name
             = link_to confirm_destroy_organization_admin_path(admin.organization, admin),
                       class:        'gh-icon-button',
-                      title:        'Usuń',
-                      'aria-label': "Usuń: #{name}",
+                      title:        t('.remove'),
+                      'aria-label': t('.remove_label', name: name),
                       data:         { turbo_frame: 'modal' } do
               %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
   - else
-    %p.gh-explainer-note Organizacja nie ma jeszcze administratora.
+    %p.gh-explainer-note= t('.none')
diff --git a/app/views/organizations/_confirm_destroy.html.haml b/app/views/organizations/_confirm_destroy.html.haml
index b3745e47..c9b6aff2 100644
--- a/app/views/organizations/_confirm_destroy.html.haml
+++ b/app/views/organizations/_confirm_destroy.html.haml
@@ -1,9 +1,9 @@
 - members = organization.users.count
 
-%h2.gh-h2 Usunąć organizację na zawsze?
+%h2.gh-h2= t('.title')
 %p
-  = "#{members} #{gh_plural(members, 'konto zostanie usunięte', 'konta zostaną usunięte', 'kont zostanie usuniętych')}"
-  razem z organizacją, w tym konta administratorów.
+  = t('.accounts', count: members)
+  = t('.accounts_tail')
 
 = form_with url: organization_path(organization), method: :delete,
   data: { controller: 'confirm-name',
@@ -12,7 +12,7 @@
 
   .gh-form-field
     = label_tag :confirm do
-      Wpisz nazwę organizacji, żeby potwierdzić:
+      = t('.confirm_label')
       %b= organization.name
     .gh-text-input{ class: ('gh-text-input--invalid' if @confirm_failed) }
       = text_field_tag :confirm, nil, autocomplete: 'off', autofocus: true,
@@ -22,14 +22,14 @@
     - if @confirm_failed
       %p#gh-del-organization-error.gh-field-error{ role: 'alert' }
         %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-        %span Wpisana nazwa nie zgadza się z nazwą organizacji. Organizacja nie została usunięta.
+        %span= t('.mismatch')
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('organizations.dialog_actions.cancel')
     - else
-      = link_to 'Anuluj', organization_path(organization), class: 'gh-btn gh-btn--secondary'
+      = link_to t('organizations.dialog_actions.cancel'), organization_path(organization), class: 'gh-btn gh-btn--secondary'
 
     %button.gh-btn{ type: 'submit', disabled: true,
                     data: { confirm_name_target: 'submit' } }
-      Usuń organizację
+      = t('.remove')
diff --git a/app/views/organizations/_dialog_actions.html.haml b/app/views/organizations/_dialog_actions.html.haml
index f12a7058..73739c52 100644
--- a/app/views/organizations/_dialog_actions.html.haml
+++ b/app/views/organizations/_dialog_actions.html.haml
@@ -2,7 +2,7 @@
 -# back to `cancel_path`.
 .gh-dialog-button-row
   - if @in_modal
-    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('.cancel')
   - else
-    = link_to 'Anuluj', cancel_path, class: 'gh-btn gh-btn--secondary'
+    = link_to t('.cancel'), cancel_path, class: 'gh-btn gh-btn--secondary'
   %button.gh-btn{ type: 'submit' }= submit_label
diff --git a/app/views/organizations/_form.html.haml b/app/views/organizations/_form.html.haml
index 755772c5..d1c0a125 100644
--- a/app/views/organizations/_form.html.haml
+++ b/app/views/organizations/_form.html.haml
@@ -1,19 +1,17 @@
 - editing = organization.persisted?
 
 = form_with model: organization, data: { turbo_frame: (@in_modal ? 'modal' : nil) } do |form|
-  %h2.gh-h2= editing ? 'Edytuj organizację' : 'Nowa organizacja'
+  %h2.gh-h2= editing ? t('.edit_title') : t('.new_title')
   - if organization.usos?
-    %p
-      To organizacja powiązana z USOS: trafia do niej każdy, kto zaloguje się
-      przez USOS. Nie ma limitu członków i nie można jej usunąć.
+    %p= t('.usos_note')
 
-  = render 'organizations/field', form: form, record: organization, attribute: :name, label: 'Nazwa',
+  = render 'organizations/field', form: form, record: organization, attribute: :name, label: t('.name'),
                                   options: { maxlength: 100, autofocus: true }
   - unless organization.usos?
     = render 'organizations/field', form: form, record: organization, attribute: :max_members,
-                                    label: 'Limit członków', input: :number_field,
+                                    label: t('.max_members'), input: :number_field,
                                     options: { min: 1, step: 1 }
 
   = render 'organizations/dialog_actions',
     cancel_path: (editing ? organization_path(organization) : organizations_path),
-    submit_label: (editing ? 'Zapisz' : 'Utwórz organizację')
+    submit_label: (editing ? t('.save') : t('.create'))
diff --git a/app/views/organizations/_member_row.html.haml b/app/views/organizations/_member_row.html.haml
index b55b9652..d2de26df 100644
--- a/app/views/organizations/_member_row.html.haml
+++ b/app/views/organizations/_member_row.html.haml
@@ -7,25 +7,25 @@
   = render 'organizations/person', user: user
 
   %span.gh-teacher-role
-    %span.gh-mobile-field-label Rola
+    %span.gh-mobile-field-label= t('.role')
     = user_role_label(user.role)
     - if user.first_login?
-      %small Zaproszenie wysłane
+      %small= t('.invited')
 
   %span
-    %span.gh-mobile-field-label Numer indeksu
+    %span.gh-mobile-field-label= t('.index_number')
     %span.gh-small= user.university_number.presence || '—'
 
   %span.gh-organization-member-actions
     - if user.first_login?
       = render 'organizations/resend_invitation_button', organization: @organization, user: user, name: name
     = link_to edit_organization_user_path(@organization, user),
-      class: 'gh-icon-button', title: 'Edytuj',
-      'aria-label': "Edytuj: #{name}",
+      class: 'gh-icon-button', title: t('.edit'),
+      'aria-label': t('.edit_label', name: name),
       data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-pen{ 'aria-hidden': 'true' }
     = link_to confirm_destroy_organization_user_path(@organization, user),
-      class: 'gh-icon-button', title: 'Usuń',
-      'aria-label': "Usuń: #{name}",
+      class: 'gh-icon-button', title: t('.remove'),
+      'aria-label': t('.remove_label', name: name),
       data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
diff --git a/app/views/organizations/_members.html.haml b/app/views/organizations/_members.html.haml
index 754afff5..fb5ac4b9 100644
--- a/app/views/organizations/_members.html.haml
+++ b/app/views/organizations/_members.html.haml
@@ -1,39 +1,37 @@
 - if users.any?
   %div{ data: { controller:              'list-search',
                 list_search_total_value: users.size,
-                list_search_of_value:    'z', } }
+                list_search_of_value:    t('.of'), } }
     .gh-student-list-toolbar
       %label.gh-search-input
         %i.fa-solid.fa-magnifying-glass{ 'aria-hidden': 'true' }
         %input{ type:         'search',
-                placeholder:  'Szukaj po nazwisku lub e-mailu',
-                'aria-label': 'Szukaj użytkownika',
+                placeholder:  t('.search_placeholder'),
+                'aria-label': t('.search_label'),
                 data:         { list_search_target: 'input', action: 'input->list-search#filter' }, }
       %span.gh-select-input
-        = select_tag :role, options_for_select(user_role_options), include_blank: 'Wszystkie role',
-          'aria-label': 'Filtruj po roli',
+        = select_tag :role, options_for_select(user_role_options), include_blank: t('.all_roles'),
+          'aria-label': t('.filter_label'),
           data: { list_search_target: 'filter', action: 'change->list-search#filter' }
         %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
       %span.gh-card-meta{ data: { list_search_target: 'count' } }
-        = "#{users.size} z #{users.size}"
+        = "#{users.size} #{t('.of')} #{users.size}"
 
     %section.gh-panel.gh-organizations-panel
       .gh-organization-member-row.gh-organization-member-row--header{ 'aria-hidden': 'true' }
-        %span Użytkownik
-        %span Rola
-        %span Numer indeksu
-        %span.gh-ledger-cell--right Akcje
+        %span= t('.user')
+        %span= t('.role')
+        %span= t('.index_number')
+        %span.gh-ledger-cell--right= t('.actions')
 
       = render partial: 'organizations/member_row', collection: users, as: :user
 
     %section.gh-panel.gh-empty-state{ hidden: true, data: { list_search_target: 'empty' } }
       %h2.gh-h2
-        Brak użytkowników pasujących do
+        = t('.no_match')
         %span{ data: { list_search_target: 'emptyQuery' } }
-      %p.gh-lead Wyczyść wyszukiwanie, zmień rolę albo sprawdź pisownię.
+      %p.gh-lead= t('.no_match_hint')
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Nie ma jeszcze użytkowników
-    %p.gh-lead
-      Dodaj studentów i nauczycieli — dostaną zaproszenie e-mailem. Konta
-      zakładane przez logowanie z uczelni pojawią się tu same.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_lead')
diff --git a/app/views/organizations/_owned_groups_notice.html.haml b/app/views/organizations/_owned_groups_notice.html.haml
index 45246382..a9c05237 100644
--- a/app/views/organizations/_owned_groups_notice.html.haml
+++ b/app/views/organizations/_owned_groups_notice.html.haml
@@ -2,9 +2,6 @@
 
 - if owned.any?
   %p.gh-explainer-note
-    - if owned.one?
-      Usunięta zostanie też grupa prowadzona przez to konto:
-    - else
-      Usunięte zostaną też grupy prowadzone przez to konto:
-    %b= owned.to_sentence(words_connector: ', ', two_words_connector: ' i ', last_word_connector: ' i ')
-    — ze wszystkimi studentami, walutą, odznakami i arkuszami ocen.
+    = t('.lead', count: owned.size)
+    %b= owned.to_sentence
+    = t('.rest')
diff --git a/app/views/organizations/_resend_invitation_button.html.haml b/app/views/organizations/_resend_invitation_button.html.haml
index 00a8a42b..8cea0b07 100644
--- a/app/views/organizations/_resend_invitation_button.html.haml
+++ b/app/views/organizations/_resend_invitation_button.html.haml
@@ -1,5 +1,5 @@
 = button_to organization_user_invitation_path(organization, user),
             class:        'gh-icon-button',
-            title:        'Wyślij zaproszenie ponownie',
-            'aria-label': "Wyślij zaproszenie ponownie: #{name}" do
+            title:        t('.title'),
+            'aria-label': t('.label', name: name) do
   %i.fa-solid.fa-paper-plane{ 'aria-hidden': 'true' }
diff --git a/app/views/organizations/_user_form.html.haml b/app/views/organizations/_user_form.html.haml
index 264ba150..944d1dcf 100644
--- a/app/views/organizations/_user_form.html.haml
+++ b/app/views/organizations/_user_form.html.haml
@@ -2,18 +2,18 @@
 - url     = editing ? organization_user_path(@organization, user) : add_user_organization_path(@organization)
 
 = form_with model: user, url: url, data: { turbo_frame: (@in_modal ? 'modal' : nil) } do |form|
-  %h2.gh-h2= editing ? 'Edytuj użytkownika' : 'Dodaj użytkownika'
+  %h2.gh-h2= editing ? t('.edit_title') : t('.new_title')
   - unless editing
-    %p Wyślemy zaproszenie na podany adres. Konto zajmie jedno miejsce w organizacji.
+    %p= t('.hint')
 
-  = render 'organizations/field', form: form, record: user, attribute: :email, label: 'Adres e-mail',
+  = render 'organizations/field', form: form, record: user, attribute: :email, label: t('.email'),
                                   input: :email_field,
-                                  options: { placeholder: 'jan.nowak@example.com', autofocus: !editing }
-  = render 'organizations/field', form: form, record: user, attribute: :full_name, label: 'Imię i nazwisko',
+                                  options: { placeholder: t('.email_placeholder'), autofocus: !editing }
+  = render 'organizations/field', form: form, record: user, attribute: :full_name, label: t('.full_name'),
                                   options: { maxlength: 80 }
 
   .gh-form-field
-    = form.label :role, 'Rola'
+    = form.label :role, t('.role')
     %span.gh-select-input
       = form.select :role, user_role_options
       %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
@@ -24,8 +24,8 @@
 
   .gh-form-row-2col
     = render 'organizations/field', form: form, record: user, attribute: :university_number,
-                                    label: 'Numer indeksu (opcjonalnie)', options: { maxlength: 20 }
-    = render 'organizations/field', form: form, record: user, attribute: :usos_id, label: 'ID USOS (opcjonalnie)'
+                                    label: t('.university_number'), options: { maxlength: 20 }
+    = render 'organizations/field', form: form, record: user, attribute: :usos_id, label: t('.usos_id')
 
   - if (error = user.errors[:organization].first)
     %p.gh-field-error{ role: 'alert' }
@@ -33,4 +33,4 @@
       %span= error
 
   = render 'organizations/dialog_actions', cancel_path: organization_path(@organization),
-                                           submit_label: (editing ? 'Zapisz' : 'Wyślij zaproszenie')
+                                           submit_label: (editing ? t('.submit_edit') : t('.submit_new'))
diff --git a/app/views/organizations/admins/_confirm_destroy.html.haml b/app/views/organizations/admins/_confirm_destroy.html.haml
index 64581a43..b0010623 100644
--- a/app/views/organizations/admins/_confirm_destroy.html.haml
+++ b/app/views/organizations/admins/_confirm_destroy.html.haml
@@ -1,18 +1,18 @@
 - name = admin.full_name.presence || admin.email
 
-%h2.gh-h2= "Usunąć administratora #{name}?"
+%h2.gh-h2= t('.title', name: name)
 %p
-  Konto zostanie usunięte na stałe i zwolni się jedno miejsce w organizacji.
+  = t('.body')
   - if admin.first_login?
-    Wysłane zaproszenie przestanie działać.
+    = t('.pending')
 = render 'organizations/owned_groups_notice', user: admin
 
 .gh-dialog-button-row
   - if @in_modal
-    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true } Anuluj
+    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }= t('organizations.dialog_actions.cancel')
   - else
-    = link_to 'Anuluj', organization_path(@organization), class: 'gh-btn gh-btn--secondary'
+    = link_to t('organizations.dialog_actions.cancel'), organization_path(@organization), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń konto', organization_admin_path(@organization, admin),
+  = button_to t('.remove'), organization_admin_path(@organization, admin),
               method: :delete, class: 'gh-btn',
               form:   { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/organizations/admins/confirm_destroy.html.haml b/app/views/organizations/admins/confirm_destroy.html.haml
index a5b867b5..d827f3ac 100644
--- a/app/views/organizations/admins/confirm_destroy.html.haml
+++ b/app/views/organizations/admins/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Usunąć administratora?'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/organizations/confirm_destroy.html.haml b/app/views/organizations/confirm_destroy.html.haml
index 733da5df..f15255bc 100644
--- a/app/views/organizations/confirm_destroy.html.haml
+++ b/app/views/organizations/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń organizację #{@organization.name}"
+- content_for :title, t('.page_title', name: @organization.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/organizations/edit.html.haml b/app/views/organizations/edit.html.haml
index fe7ac1e5..f85e264f 100644
--- a/app/views/organizations/edit.html.haml
+++ b/app/views/organizations/edit.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Edytuj organizację — #{@organization.name}"
+- content_for :title, t('.page_title', name: @organization.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/organizations/index.html.haml b/app/views/organizations/index.html.haml
index 8104e8cd..cc0cf86d 100644
--- a/app/views/organizations/index.html.haml
+++ b/app/views/organizations/index.html.haml
@@ -1,37 +1,33 @@
-- content_for :title, 'Organizacje'
+- content_for :title, t('.title')
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Organizacje
-    %p.gh-lead
-      Uczelnie korzystające z aplikacji. Konta logujące się przez USOS trafiają
-      do organizacji #{Organization::USOS_NAME}.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead', usos: Organization::USOS_NAME)
 
   - if policy(:organization).create?
     = link_to new_organization_path, class: 'gh-btn', data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      Utwórz organizację
+      = t('.create')
 
 - if @organizations.any?
   %section.gh-panel.gh-organizations-panel
     .gh-organization-row.gh-organization-row--header{ 'aria-hidden': 'true' }
-      %span Organizacja
-      %span Członkowie
-      %span Administratorzy
+      %span= t('.organization')
+      %span= t('.members')
+      %span= t('.admins')
 
     - @organizations.each do |organization|
       - members = @member_counts.fetch(organization.id, 0)
       = link_to organization_path(organization), class: 'gh-organization-row gh-organization-row--link' do
         %b.gh-organization-name= organization.name
         %span
-          %span.gh-mobile-field-label Członkowie
+          %span.gh-mobile-field-label= t('.members')
           %span.gh-numeric-cell= "#{members} / #{organization.max_members || '-'}"
         %span
-          %span.gh-mobile-field-label Administratorzy
+          %span.gh-mobile-field-label= t('.admins')
           %span.gh-numeric-cell= @admin_counts.fetch(organization.id, 0)
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Nie ma jeszcze żadnej organizacji
-    %p.gh-lead
-      Utwórz organizację, a potem dodaj jej administratora —
-      on zaprosi resztę osób.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_lead')
diff --git a/app/views/organizations/new.html.haml b/app/views/organizations/new.html.haml
index 220b39ed..5f50fb53 100644
--- a/app/views/organizations/new.html.haml
+++ b/app/views/organizations/new.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Nowa organizacja'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/organizations/new_admin.html.haml b/app/views/organizations/new_admin.html.haml
index 9115f358..3e3edce6 100644
--- a/app/views/organizations/new_admin.html.haml
+++ b/app/views/organizations/new_admin.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Dodaj administratora organizacji'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/organizations/new_user.html.haml b/app/views/organizations/new_user.html.haml
index 4f3c2c6e..4766f94f 100644
--- a/app/views/organizations/new_user.html.haml
+++ b/app/views/organizations/new_user.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Dodaj użytkownika organizacji'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/organizations/show.html.haml b/app/views/organizations/show.html.haml
index eb893f87..d4a902ff 100644
--- a/app/views/organizations/show.html.haml
+++ b/app/views/organizations/show.html.haml
@@ -6,7 +6,7 @@
   .gh-page-header-text
     - if @current_user.global_admin?
       %p.gh-breadcrumbs
-        = link_to 'Organizacje', organizations_path
+        = link_to t('.breadcrumb'), organizations_path
         %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
         %span= @organization.name
     %h1.gh-h1= @organization.name
@@ -17,15 +17,15 @@
       = link_to edit_organization_path(@organization), class: 'gh-btn gh-btn--secondary',
                                                        data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-pen{ 'aria-hidden': 'true' }
-        Edytuj
+        = t('.edit')
     - if policy(@organization).new_admin?
       = link_to new_admin_organization_path(@organization), class: 'gh-btn', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-user-shield{ 'aria-hidden': 'true' }
-        Dodaj administratora
+        = t('.add_admin')
     - if manage_users
       = link_to new_user_organization_path(@organization), class: 'gh-btn', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-user-plus{ 'aria-hidden': 'true' }
-        Dodaj użytkownika
+        = t('.add_user')
 
 = render 'admins', admins: @admins, manage_admins: policy(@organization).manage_admins?
 
@@ -34,10 +34,10 @@
 
 - if policy(@organization).destroy?
   %section.gh-panel.gh-danger-zone
-    %h2.gh-h3 Usuń organizację
-    %p.gh-small Razem z organizacją znikną wszystkie jej konta. Tej operacji nie można cofnąć.
+    %h2.gh-h3= t('.danger_title')
+    %p.gh-small= t('.danger_body')
     .gh-button-row
       = link_to confirm_destroy_organization_path(@organization),
         class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-        Usuń organizację
+        = t('.danger_button')
diff --git a/app/views/organizations/users/_confirm_destroy.html.haml b/app/views/organizations/users/_confirm_destroy.html.haml
index cdb70ad7..abc29d51 100644
--- a/app/views/organizations/users/_confirm_destroy.html.haml
+++ b/app/views/organizations/users/_confirm_destroy.html.haml
@@ -1,15 +1,13 @@
-%h2.gh-h2= "Usunąć konto #{user.full_name}?"
-%p
-  Konto zostanie usunięte na stałe, razem z członkostwem w grupach, walutą,
-  odznakami i przedmiotami. Zwolni się jedno miejsce w organizacji.
+%h2.gh-h2= t('.title', name: user.full_name)
+%p= t('.body')
 = render 'organizations/owned_groups_notice', user: user
 
 .gh-dialog-button-row
   - if @in_modal
-    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true } Anuluj
+    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }= t('organizations.dialog_actions.cancel')
   - else
-    = link_to 'Anuluj', organization_path(@organization), class: 'gh-btn gh-btn--secondary'
+    = link_to t('organizations.dialog_actions.cancel'), organization_path(@organization), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń konto', organization_user_path(@organization, user),
+  = button_to t('.remove'), organization_user_path(@organization, user),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/organizations/users/confirm_destroy.html.haml b/app/views/organizations/users/confirm_destroy.html.haml
index d83d4842..a0781f9b 100644
--- a/app/views/organizations/users/confirm_destroy.html.haml
+++ b/app/views/organizations/users/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usunąć konto #{@user.full_name}?"
+- content_for :title, t('.page_title', name: @user.full_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/organizations/users/edit.html.haml b/app/views/organizations/users/edit.html.haml
index d3b3ab4e..46f909fe 100644
--- a/app/views/organizations/users/edit.html.haml
+++ b/app/views/organizations/users/edit.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Edytuj użytkownika — #{@user.full_name}"
+- content_for :title, t('.page_title', name: @user.full_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/passwordless_mailer/token_email.html.haml b/app/views/passwordless_mailer/token_email.html.haml
index a9885e83..f4d83431 100644
--- a/app/views/passwordless_mailer/token_email.html.haml
+++ b/app/views/passwordless_mailer/token_email.html.haml
@@ -6,21 +6,21 @@
           %td{ style: 'padding:32px;font-family:Helvetica,Arial,sans-serif;' }
             %p{ style: 'margin:0 0 28px;font:800 18px/1 Helvetica,Arial,sans-serif;color:#221A2B;' } Gamification Hub
 
-            %h1{ style: 'margin:0 0 16px;font-size:22px;color:#221A2B;' } Zaloguj się
+            %h1{ style: 'margin:0 0 16px;font-size:22px;color:#221A2B;' }= t('.title')
             %p{ style: 'margin:0 0 12px;font-size:15px;line-height:1.5;color:#584C64;' }
-              = "Cześć, #{@first_name}!"
+              = t('.greeting', name: @first_name)
             %p{ style: 'margin:0 0 24px;font-size:15px;line-height:1.5;color:#584C64;' }
-              Kliknij przycisk poniżej, aby zalogować się. Hasło nie jest potrzebne.
+              = t('.body')
 
             %table{ cellpadding: 0, cellspacing: 0, border: 0 }
               %tr
                 %td{ style: 'background:#FF7A1A;border-bottom:3px solid #C45A10;', align: 'center' }
-                  %a{ href: @token_link, style: 'display:inline-block;padding:14px 28px;font:700 15px Helvetica,Arial,sans-serif;color:#221A2B;text-decoration:none;' } Zaloguj się
+                  %a{ href: @token_link, style: 'display:inline-block;padding:14px 28px;font:700 15px Helvetica,Arial,sans-serif;color:#221A2B;text-decoration:none;' }= t('.button')
 
             %p{ style: 'margin:24px 0 0;font-size:13px;line-height:1.5;color:#85798F;' }
-              = "Link jest ważny przez #{gh_minutes(@expires_in_minutes)}. Jeśli przycisk nie działa, skopiuj ten adres do przeglądarki:"
+              = t('.fallback', minutes: gh_minutes(@expires_in_minutes))
             %p{ style: 'margin:8px 0 0;font-size:13px;word-break:break-all;' }
               %a{ href: @token_link, style: 'color:#584C64;' }= @token_link
 
             %p{ style: 'margin:28px 0 0;padding-top:16px;border-top:1px solid #E4DCEA;font-size:12.5px;color:#85798F;' }
-              Jeśli to nie Ty próbowałeś się zalogować, możesz zignorować tę wiadomość.
+              = t('.ignore')
diff --git a/app/views/passwordless_mailer/token_email.text.haml b/app/views/passwordless_mailer/token_email.text.haml
index b22d6b2a..74ad0019 100644
--- a/app/views/passwordless_mailer/token_email.text.haml
+++ b/app/views/passwordless_mailer/token_email.text.haml
@@ -1,11 +1,11 @@
 Gamification Hub
 
-= "Cześć, #{@first_name}!"
+= t('.greeting', name: @first_name)
 
-Aby zalogować się, otwórz poniższy link. Hasło nie jest potrzebne.
+= t('.text_body')
 
 = @token_link
 
-= "Link jest ważny przez #{gh_minutes(@expires_in_minutes)}."
+= t('.valid_for', minutes: gh_minutes(@expires_in_minutes))
 
-Jeśli to nie Ty próbowałeś się zalogować, możesz zignorować tę wiadomość.
+= t('.ignore')
diff --git a/app/views/ranking/_board.html.haml b/app/views/ranking/_board.html.haml
index 00cb5b77..5b631e32 100644
--- a/app/views/ranking/_board.html.haml
+++ b/app/views/ranking/_board.html.haml
@@ -1,32 +1,32 @@
-%section.gh-panel.gh-ranking-table{ role: 'table', 'aria-label': 'Ranking' }
+%section.gh-panel.gh-ranking-table{ role: 'table', 'aria-label': t('.table_label') }
   .gh-ranking-row.gh-ranking-row--header{ role: 'row' }
-    %span{ role: 'columnheader' } Miejsce
-    %span{ role: 'columnheader' }= reveal_names ? 'Pseudonim i student' : 'Pseudonim'
-    %span{ role: 'columnheader' } Ranga
-    %span.gh-ranking-score{ role: 'columnheader' } Zebrane
+    %span{ role: 'columnheader' }= t('.place')
+    %span{ role: 'columnheader' }= reveal_names ? t('.nickname_and_student') : t('.nickname')
+    %span{ role: 'columnheader' }= t('.rank')
+    %span.gh-ranking-score{ role: 'columnheader' }= t('.collected')
 
   - board.visible_rows.each do |row|
     - if row.gap?
       .gh-ranking-row.gh-ranking-row--hidden-gap{ role: 'row' }
         %span.gh-ranking-gap-label{ role: 'cell' } …
         %span.gh-ranking-name{ role: 'cell' }
-          %span.gh-empty-note Pozostałe miejsca są ukryte
+          %span.gh-empty-note= t('.hidden_rows')
     - else
       .gh-ranking-row{ class: ('gh-ranking-row--me' if row.mine), role: 'row' }
         %span{ role: 'cell' }
           %span.gh-position-badge.gh-octagon-clip{ class: ("gh-position-badge--p#{row.place}" if row.place <= 3),
-                        'aria-label': "Miejsce #{row.place}" }= row.place
+                        'aria-label': t('.place_label', place: row.place) }= row.place
 
         %span.gh-ranking-name{ role: 'cell' }
           %b
             = row.student.display_name
             - if row.mine
-              %span.gh-you-badge.gh-octagon-clip Ty
+              %span.gh-you-badge.gh-octagon-clip= t('.you')
           - if reveal_names
             - if row.student.nickname.present?
               %small= row.student.full_name
             - else
-              %small.gh-empty-note Bez pseudonimu
+              %small.gh-empty-note= t('.no_nickname')
 
         %span.gh-ranking-rank-cell{ role: 'cell' }= row.rank&.name || '—'
         %span.gh-ranking-score{ role: 'cell' }= row.student.total_currency
diff --git a/app/views/ranking/_confirm_mode.html.haml b/app/views/ranking/_confirm_mode.html.haml
index ace43d7f..dbfb323c 100644
--- a/app/views/ranking/_confirm_mode.html.haml
+++ b/app/views/ranking/_confirm_mode.html.haml
@@ -1,25 +1,21 @@
 - full = mode == 'full'
 
 - if full
-  %h2#gh-rk-title.gh-h2 Pokazać pełny ranking?
-  %p
-    Każdy student zobaczy miejsca i pseudonimy wszystkich, także osób na końcu
-    listy.
+  %h2#gh-rk-title.gh-h2= t('.full_title')
+  %p= t('.full_body')
 - else
-  %h2#gh-rk-title.gh-h2 Ograniczyć ranking do podium?
-  %p
-    Studentom zostaną pierwsze 3 miejsca i ich własne. Nikt nie zobaczy, kto
-    jest na końcu listy.
+  %h2#gh-rk-title.gh-h2= t('.podium_title')
+  %p= t('.podium_body')
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      = full ? 'Zostaw podium' : 'Anuluj'
+      = full ? t('.keep_podium') : t('shared.actions.cancel')
   - else
-    = link_to (full ? 'Zostaw podium' : 'Anuluj'), story_group_ranking_path(story_group),
+    = link_to (full ? t('.keep_podium') : t('shared.actions.cancel')), story_group_ranking_path(story_group),
       class: 'gh-btn gh-btn--secondary'
 
-  = button_to (full ? 'Pokaż pełny ranking' : 'Pokaż tylko podium'),
+  = button_to (full ? t('.show_full') : t('.show_podium')),
     story_group_ranking_path(story_group),
     method: :patch, class: 'gh-btn',
     params: { story_group: { ranking_mode: mode } },
diff --git a/app/views/ranking/_confirm_visibility.html.haml b/app/views/ranking/_confirm_visibility.html.haml
index 1cf6c783..bad94bbd 100644
--- a/app/views/ranking/_confirm_visibility.html.haml
+++ b/app/views/ranking/_confirm_visibility.html.haml
@@ -1,47 +1,41 @@
-
 - if enabled
-  %h2#gh-rk-title.gh-h2 Pokazać ranking studentom?
-  %p Studenci zobaczą ranking od razu. Wybierz, ile mają widzieć.
+  %h2#gh-rk-title.gh-h2= t('.show_title')
+  %p= t('.show_body')
 
   = form_with model: story_group, url: story_group_ranking_path(story_group), method: :patch,
     data: { turbo_frame: (@in_modal ? 'modal' : nil) } do |f|
     = f.hidden_field :ranking_enabled, value: true
 
-    .gh-choice-grid.gh-ranking-mode-options{ role: 'radiogroup', 'aria-label': 'Co widzą studenci' }
+    .gh-choice-grid.gh-ranking-mode-options{ role: 'radiogroup', 'aria-label': t('.modes_label') }
       %label.gh-choice-card
         = f.radio_button :ranking_mode, 'podium_and_own', checked: mode == 'podium_and_own',
           class: 'sr-only'
-        %b= StoryGroup::RANKING_MODE_LABELS.fetch('podium_and_own')
-        %span
-          Wszyscy widzą pierwsze 3 miejsca. Każdy widzi też swoje miejsce, ale
-          nie cudze.
+        %b= StoryGroup.ranking_mode_label('podium_and_own')
+        %span= t('.podium_body')
       %label.gh-choice-card
         = f.radio_button :ranking_mode, 'full', checked: mode == 'full', class: 'sr-only'
-        %b= StoryGroup::RANKING_MODE_LABELS.fetch('full')
-        %span
-          Wszyscy widzą miejsca i pseudonimy wszystkich, także na końcu listy.
+        %b= StoryGroup.ranking_mode_label('full')
+        %span= t('.full_body')
 
     .gh-dialog-button-row
       - if @in_modal
-        %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+        %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
       - else
-        = link_to 'Anuluj', story_group_ranking_path(story_group), class: 'gh-btn gh-btn--secondary'
+        = link_to t('shared.actions.cancel'), story_group_ranking_path(story_group), class: 'gh-btn gh-btn--secondary'
 
-      %button.gh-btn{ type: 'submit', autofocus: true } Pokaż ranking
+      %button.gh-btn{ type: 'submit', autofocus: true }= t('.show')
 - else
-  %h2#gh-rk-title.gh-h2 Ukryć ranking przed studentami?
-  %p
-    Studenci przestaną widzieć miejsca i pseudonimy. Ty nadal widzisz cały
-    ranking, a zebrana waluta i rangi nie zmieniają się.
+  %h2#gh-rk-title.gh-h2= t('.hide_title')
+  %p= t('.hide_body')
 
   .gh-dialog-button-row
     - if @in_modal
       %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-        Zostaw widoczny
+        = t('.keep_visible')
     - else
-      = link_to 'Zostaw widoczny', story_group_ranking_path(story_group), class: 'gh-btn gh-btn--secondary'
+      = link_to t('.keep_visible'), story_group_ranking_path(story_group), class: 'gh-btn gh-btn--secondary'
 
-    = button_to 'Ukryj ranking', story_group_ranking_path(story_group),
+    = button_to t('.hide'), story_group_ranking_path(story_group),
       method: :patch, class: 'gh-btn',
       params: { story_group: { ranking_enabled: false } },
       form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/ranking/_student_board.html.haml b/app/views/ranking/_student_board.html.haml
index be63b9f3..c75e9fcc 100644
--- a/app/views/ranking/_student_board.html.haml
+++ b/app/views/ranking/_student_board.html.haml
@@ -1,32 +1,32 @@
 - story_group = board.story_group
 
 %section.gh-panel.gh-page-header.gh-page-header--stacked
-  %h1.gh-h1 Ranking
+  %h1.gh-h1= t('.title')
   %p.gh-lead
     - if !board.visible?
-      Prowadzący ukrył ranking na razie.
+      = t('.hidden_lead')
     - elsif story_group.ranking_podium_and_own?
-      Prowadzący pokazuje tylko podium. Swoje miejsce widzisz tylko Ty.
+      = t('.podium_lead')
     - else
-      = "Kolejność według łącznie zebranej waluty (#{story_group.currency_name})."
+      = t('.full_lead', currency: story_group.currency_name)
 
   .gh-my-ranking-stats
     - if board.own_place
       %div
-        %b= "#{board.own_place}."
-        %small= "Twoje miejsce z #{board.participants_count}"
+        %b= t('.own_place', place: board.own_place)
+        %small= t('.own_place_label', count: board.participants_count)
 
     %div
       %b= board.own_row.student.total_currency
-      %small Zebrane łącznie
+      %small= t('.collected')
 
     .gh-nickname-row
-      Twój pseudonim w tej grupie:
-      %b= board.membership.nickname.presence || 'brak'
+      = t('.nickname')
+      %b= board.membership.nickname.presence || t('.no_nickname')
       = link_to nickname_story_group_membership_path(story_group),
         class: 'gh-link-button', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-pen{ 'aria-hidden': 'true' }
-        Zmień
+        = t('.change')
 
 - if board.visible?
   = render 'board', board: board, reveal_names: false
@@ -34,7 +34,5 @@
   %section.gh-panel.gh-empty-state
     .gh-empty-state-icon.gh-octagon-clip
       %i.fa-solid.fa-eye-slash{ 'aria-hidden': 'true' }
-    %h2.gh-h2 Ranking jest teraz ukryty
-    %p.gh-lead
-      Zbieraj dalej walutę. Gdy prowadzący włączy ranking, zobaczysz tu swoje
-      miejsce.
+    %h2.gh-h2= t('.hidden_title')
+    %p.gh-lead= t('.hidden_body')
diff --git a/app/views/ranking/_teacher_board.html.haml b/app/views/ranking/_teacher_board.html.haml
index 37d811c9..4a0d2833 100644
--- a/app/views/ranking/_teacher_board.html.haml
+++ b/app/views/ranking/_teacher_board.html.haml
@@ -2,10 +2,8 @@
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Ranking
-    %p.gh-lead
-      = "Kolejność według łącznie zebranej waluty (#{story_group.currency_name})."
-      Studenci widzą tylko pseudonimy, Ty widzisz też imiona i nazwiska.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead', currency: story_group.currency_name)
 
   .gh-ranking-controls
     .gh-toggle-switch-row.gh-switch-row--inline
@@ -15,11 +13,12 @@
         'aria-checked': board.visible?.to_s, 'aria-labelledby': 'gh-rk-vis',
         data: { turbo_frame: 'modal' }
       %span
-        %b#gh-rk-vis Widoczny dla studentów
+        %b#gh-rk-vis= t('.visible')
 
     - if board.visible?
-      .gh-segmented-toggle-2.gh-octagon-clip{ role: 'group', 'aria-label': 'Co widzą studenci' }
-        - StoryGroup::RANKING_MODE_LABELS.each do |mode, label|
+      .gh-segmented-toggle-2.gh-octagon-clip{ role: 'group', 'aria-label': t('.modes_label') }
+        - StoryGroup.ranking_modes.each_key do |mode|
+          - label = StoryGroup.ranking_mode_label(mode)
           - if story_group.ranking_mode == mode
             %span{ 'aria-pressed': 'true' }= label
           - else
@@ -30,27 +29,24 @@
   %p.gh-info-banner.gh-ranking-visibility-note
     %i.fa-solid.fa-eye-slash{ 'aria-hidden': 'true' }
     %span
-      %b Ranking jest ukryty przed studentami.
-      Ty nadal go widzisz.
+      %b= t('.hidden_note')
+      = t('.hidden_note_tail')
 - elsif story_group.ranking_podium_and_own?
   %p.gh-info-banner.gh-ranking-visibility-note
     %i.fa-solid.fa-eye-slash{ 'aria-hidden': 'true' }
     %span
-      %b Studenci widzą tylko podium i swoje miejsce.
-      Nikt nie zobaczy, kto jest na końcu listy. Ty widzisz wszystkich.
+      %b= t('.podium_note')
+      = t('.podium_note_tail')
 
 - if board.any?
   = render 'board', board: board, reveal_names: true
 
-  %p.gh-small.gh-ranking-footnote
-    Remis daje to samo miejsce.
-    Studenci bez pseudonimu są widoczni pod imieniem i nazwiskiem.
+  %p.gh-small.gh-ranking-footnote= t('.footnote')
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Nikt jeszcze nie dołączył do grupy
-    %p.gh-lead
-      Ranking ułoży się sam, gdy studenci dołączą i zaczną zbierać walutę.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
     .gh-button-row
       = link_to story_group_invites_path(story_group), class: 'gh-btn' do
         %i.fa-solid.fa-qrcode
-        Zaproszenia
+        = t('.invites')
diff --git a/app/views/ranking/confirm_mode.html.haml b/app/views/ranking/confirm_mode.html.haml
index 1333c647..7fddbbea 100644
--- a/app/views/ranking/confirm_mode.html.haml
+++ b/app/views/ranking/confirm_mode.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Ranking - #{StoryGroup::RANKING_MODE_LABELS.fetch(@mode)}"
+- content_for :title, t('.page_title', mode: StoryGroup.ranking_mode_label(@mode))
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/ranking/confirm_visibility.html.haml b/app/views/ranking/confirm_visibility.html.haml
index 680f6533..5e4ba16b 100644
--- a/app/views/ranking/confirm_visibility.html.haml
+++ b/app/views/ranking/confirm_visibility.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, @enabled ? 'Pokaż ranking' : 'Ukryj ranking'
+- content_for :title, @enabled ? t('.show_page_title') : t('.hide_page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/ranking/show.html.haml b/app/views/ranking/show.html.haml
index e4dab000..28bec0c5 100644
--- a/app/views/ranking/show.html.haml
+++ b/app/views/ranking/show.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Ranking - #{@story_group.name}"
+- content_for :title, t('.page_title', group: @story_group.name)
 
 - if @board.teacher?
   = render 'teacher_board', board: @board
diff --git a/app/views/ranks/_confirm_destroy.html.haml b/app/views/ranks/_confirm_destroy.html.haml
index d2156e4f..b24fac63 100644
--- a/app/views/ranks/_confirm_destroy.html.haml
+++ b/app/views/ranks/_confirm_destroy.html.haml
@@ -1,25 +1,21 @@
-%h2#gh-del-title.gh-h2= "Usunąć rangę „#{rank.name}”?"
-%p Studenci z tą rangą spadną do rangi niżej.
+%h2#gh-del-title.gh-h2= t('.title', name: rank.name)
+%p= t('.body')
 
 - if dependent_items.any?
-  - one = dependent_items.one?
   %p.gh-warning-note{ role: 'alert' }
     %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-    %span
-      = "#{one ? 'Przedmiot' : 'Przedmioty'} #{gh_and_list(dependent_items.map(&:name))}"
-      = one ? 'wymaga tej rangi.' : 'wymagają tej rangi.'
-      = "Zanim ją usuniesz, przypisz #{one ? 'mu' : 'im'} inną rangę."
+    %span= t('.blocked', count: dependent_items.size, items: gh_and_list(dependent_items.map(&:name)))
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', edit_story_group_rank_path(@story_group, rank), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), edit_story_group_rank_path(@story_group, rank), class: 'gh-btn gh-btn--secondary'
 
   - if dependent_items.any?
-    %button.gh-btn{ type: 'button', disabled: true } Usuń rangę
+    %button.gh-btn{ type: 'button', disabled: true }= t('.remove')
   - else
-    = button_to 'Usuń rangę', story_group_rank_path(@story_group, rank),
+    = button_to t('.remove'), story_group_rank_path(@story_group, rank),
       method: :delete, class: 'gh-btn',
       form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/ranks/_form.html.haml b/app/views/ranks/_form.html.haml
index c0ea337d..a3139d89 100644
--- a/app/views/ranks/_form.html.haml
+++ b/app/views/ranks/_form.html.haml
@@ -3,15 +3,15 @@
 
 %section.gh-panel.gh-page-header.gh-page-header--stacked
   %p.gh-breadcrumbs
-    = link_to 'Rangi', story_group_ranks_path(@story_group)
+    = link_to t('.breadcrumb'), story_group_ranks_path(@story_group)
     %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
-    %span= editing ? (rank.name_was.presence || rank.name) : 'Nowa ranga'
-  %h1.gh-h1= editing ? 'Edytuj rangę' : 'Nowa ranga'
-  %p.gh-lead
-    Podgląd obok pokazuje, gdzie ranga trafi na drabince i ilu studentów obejmie.
+    %span= editing ? (rank.name_was.presence || rank.name) : t('.new_title')
+  %h1.gh-h1= editing ? t('.edit_title') : t('.new_title')
+  %p.gh-lead= t('.lead')
 
 - rungs_json = ladder.rungs.map { |rung| { id: rung.rank.id, name: rung.rank.name, min: rung.rank.required_currency_value.to_i, disc: rung.rank.discount.to_i } }.to_json
-- form_data = { controller: 'rank-form', action: 'gh:image-crop->rank-form#art', rank_form_rungs_value: rungs_json, rank_form_totals_value: ladder.student_totals.to_json, rank_form_editing_id_value: rank.id.to_i }
+- i18n_json  = t('ranks.helpers').slice(:required, :gives_discount, :discount, :starting, :no_discount, :name_placeholder, :new_rank, :from_short).merge(t('.js')).to_json
+- form_data = { controller: 'rank-form', action: 'gh:image-crop->rank-form#art', rank_form_rungs_value: rungs_json, rank_form_totals_value: ladder.student_totals.to_json, rank_form_editing_id_value: rank.id.to_i, rank_form_i18n_value: i18n_json }
 
 = form_with model: [@story_group, rank], data: form_data do |f|
 
@@ -22,19 +22,18 @@
         %p.gh-info-banner
           %i.fa-solid.fa-users{ 'aria-hidden': 'true' }
           %span
-            %b
-              = "#{holders} #{gh_plural(holders, 'student ma', 'studentów ma', 'studentów ma')} tę rangę."
-            Zmiana progu może przesunąć studentów w górę lub w dół. Podgląd obok pokazuje skutki.
+            %b= t('.holders', count: holders)
+            = t('.holders_note')
 
       .gh-form-section
-        %h2.gh-h3 Karta rangi
-        %p.gh-field-hint Tak ranga wygląda na stronie grupy i w rankingu.
+        %h2.gh-h3= t('.card')
+        %p.gh-field-hint= t('.card_hint')
 
         .gh-form-field
-          = f.label :name, 'Nazwa'
+          = f.label :name, t('shared.actions.name')
           .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:name)) }
             = f.text_field :name, maxlength: 40, autocomplete: 'off',
-              placeholder: 'np. Admirał Floty',
+              placeholder: t('.name_placeholder'),
               'aria-invalid': (error.call(:name) ? 'true' : nil),
               'aria-describedby': (error.call(:name) ? 'gh-rank-name-error' : nil),
               data: { rank_form_target: 'name', action: 'rank-form#refresh' }
@@ -48,13 +47,12 @@
           refresh_action: 'rank-form#refresh'
 
       .gh-form-section
-        %h2.gh-h3 Próg i nagroda
-        %p.gh-field-hint
-          Ranga zależy od łącznie zebranej waluty, więc wydawanie jej nie obniża rangi.
+        %h2.gh-h3= t('.threshold_section')
+        %p.gh-field-hint= t('.threshold_hint')
 
         .gh-form-row-2col
           .gh-form-field
-            = f.label :required_currency_value, 'Wymagane zebrane'
+            = f.label :required_currency_value, t('.threshold')
             .gh-price-field-row
               .gh-text-input.gh-text-input--numeric{ class: ('gh-text-input--invalid' if error.call(:required_currency_value)) }
                 = f.number_field :required_currency_value, min: 0, step: 1,
@@ -64,7 +62,7 @@
               = render 'layouts/currency_token', story_group: @story_group, size: 32
 
           .gh-form-field
-            = f.label :discount, 'Zniżka w sklepie'
+            = f.label :discount, t('.discount')
             .gh-price-field-row
               .gh-text-input.gh-text-input--numeric{ class: ('gh-text-input--invalid' if error.call(:discount)) }
                 = f.number_field :discount, min: 0, max: 100, step: 1,
@@ -87,23 +85,21 @@
 
       - if editing
         .gh-form-section
-          %h2.gh-h3 Usuwanie
-          %p.gh-field-hint
-            Studenci z tą rangą spadną do rangi niżej. Przedmioty, które jej wymagają,
-            trzeba będzie najpierw przypisać do innej rangi.
+          %h2.gh-h3= t('shared.actions.removal')
+          %p.gh-field-hint= t('.removal_hint')
           .gh-button-row
             = link_to confirm_destroy_story_group_rank_path(@story_group, rank),
               class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
               %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-              Usuń rangę
+              = t('.remove')
 
-    %aside.gh-preview-column{ 'aria-label': 'Podgląd' }
+    %aside.gh-preview-column{ 'aria-label': t('shared.actions.preview') }
       = render 'preview', rank: rank, ladder: ladder, editing: editing
 
   .gh-panel.gh-form-actions-bar
-    = link_to 'Anuluj', story_group_ranks_path(@story_group), class: 'gh-link-button'
+    = link_to t('shared.actions.cancel'), story_group_ranks_path(@story_group), class: 'gh-link-button'
     %span.gh-form-actions-spacer
     %button.gh-btn{ type: 'submit' }
       - unless editing
         %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      = editing ? 'Zapisz zmiany' : 'Dodaj rangę'
+      = editing ? t('shared.actions.save_changes') : t('.create')
diff --git a/app/views/ranks/_preview.html.haml b/app/views/ranks/_preview.html.haml
index d6d7e4d5..c71790c6 100644
--- a/app/views/ranks/_preview.html.haml
+++ b/app/views/ranks/_preview.html.haml
@@ -4,11 +4,11 @@
 
 %details.gh-preview-details{ open: true }
   %summary
-    Podgląd rangi
+    = t('.summary')
     %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
   %section.gh-panel.gh-preview-panel
-    %h3 Karta rangi
+    %h3= t('.card')
     .gh-preview-flip-card
       %article.gh-card.gh-card--rank
         .gh-card-frame
@@ -16,7 +16,7 @@
             .gh-card-header
               %h4.gh-card-name{ class: ('gh-placeholder-text' if rank.name.blank?),
                                 data: { rank_form_target: 'cardName' } }
-                = rank.name.presence || 'Nazwa rangi'
+                = rank.name.presence || t('ranks.helpers.name_placeholder')
             .gh-card-art{ data: { rank_form_target: 'cardArt' } }
               - if rank.upload?
                 = image_tag rank.icon, alt: ''
@@ -25,7 +25,7 @@
             %p.gh-rule-text{ data: { rank_form_target: 'cardRules' } }= rank_reward_line(rank)
 
   %section.gh-panel.gh-preview-panel
-    %h3 Drabinka rang
+    %h3= t('.ladder')
     %ol.gh-rank-form-ladder{ data: { rank_form_target: 'ladder' } }
       - entries.each do |entry, draft|
         %li.gh-rank-form-rung{ class: ('gh-rank-form-rung--draft' if draft),
@@ -36,10 +36,10 @@
           %span
             %b
               %span{ data: (draft ? { rank_form_target: 'draftName' } : {}) }
-                = entry.name.presence || 'Nowa ranga'
+                = entry.name.presence || t('ranks.helpers.new_rank')
               - if draft
-                %small (ta ranga)
+                %small= t('.this_rank')
             %small{ data: (draft ? { rank_form_target: 'draftTerms' } : {}) }
               = rank_ladder_terms(entry)
           %span.gh-rank-form-rung-value{ data: (draft ? { rank_form_target: 'draftValue' } : {}) }
-            = "od #{entry.required_currency_value.to_i}"
+            = t('ranks.helpers.from_short', min: entry.required_currency_value.to_i)
diff --git a/app/views/ranks/_student_ladder.html.haml b/app/views/ranks/_student_ladder.html.haml
index 6e628c5e..f809ee97 100644
--- a/app/views/ranks/_student_ladder.html.haml
+++ b/app/views/ranks/_student_ladder.html.haml
@@ -1,8 +1,7 @@
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Rangi
-    %p.gh-lead
-      Ranga rośnie razem z łącznie zebraną walutą. Wydawanie jej nie obniża rangi.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead')
 
 - if ladder.any?
   %ol.gh-panel.gh-student-ladder-list
@@ -13,36 +12,34 @@
           %b
             = rung.rank.name
             - if rung.current?
-              %span.gh-you-badge.gh-octagon-clip Twoja ranga
+              %span.gh-you-badge.gh-octagon-clip= t('.yours')
           %small.gh-small= rank_summary_sentences(rung.rank)
 
         %div
           - if rung.done?
             %span.gh-rank-status.gh-rank-status--achieved
               %i.fa-solid.fa-check{ 'aria-hidden': 'true' }
-              Zdobyta
+              = t('.achieved')
           - elsif rung.progressing?
             - collected, needed = rung.progress
             %span.gh-rank-status
               - if rung.next?
-                = "#{collected} z #{needed} do pierwszej rangi"
+                = t('.to_first', collected: collected, needed: needed)
               - else
-                = "#{ladder.collected} z #{rung.next_threshold} do następnej"
+                = t('.to_next', collected: ladder.collected, needed: rung.next_threshold)
             .gh-progress-bar.gh-octagon-clip{ role: 'progressbar',
                      'aria-valuemin': 0,
                      'aria-valuemax': needed,
                      'aria-valuenow': collected,
-                     'aria-label': "Postęp do rangi wyżej niż #{rung.rank.name}" }
+                     'aria-label': t('.progress_label', name: rung.rank.name) }
               %i.gh-octagon-clip{ style: "--gh-p: #{gh_percent(collected, needed)}%" }
           - elsif rung.current?
-            %span.gh-rank-status.gh-rank-status--achieved Najwyższa ranga
+            %span.gh-rank-status.gh-rank-status--achieved= t('.top')
           - else
             %span.gh-rank-status
               %i.fa-solid.fa-lock{ 'aria-hidden': 'true' }
-              = "Brakuje #{rung.remaining}"
+              = t('.missing', count: rung.remaining)
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 W tej grupie nie ma jeszcze rang
-    %p.gh-lead
-      Prowadzący ich nie dodał. Zbieraj walutę — kiedy rangi się pojawią, zaliczy
-      się wszystko, co zebrałeś do tej pory.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/ranks/_teacher_ladder.html.haml b/app/views/ranks/_teacher_ladder.html.haml
index 4092b86b..3e55639a 100644
--- a/app/views/ranks/_teacher_ladder.html.haml
+++ b/app/views/ranks/_teacher_ladder.html.haml
@@ -1,14 +1,12 @@
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Rangi
-    %p.gh-lead
-      = "#{ladder.size} #{gh_plural(ladder.size, 'ranga', 'rangi', 'rang')}."
-      Ranga zależy od łącznie zebranej waluty, więc wydawanie jej nie obniża rangi.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead', count: ladder.size)
 
   .gh-button-row
     = link_to new_story_group_rank_path(@story_group), class: 'gh-btn' do
       %i.fa-solid.fa-plus
-      Nowa ranga
+      = t('.new')
 
 - if ladder.any?
   %section.gh-panel.gh-list-panel
@@ -16,7 +14,7 @@
       - ladder.descending.each_with_index do |rung, position|
         - if position.positive?
           %li.gh-rank-gap{ 'aria-hidden': 'true' }
-            = "↑ #{rung.gap_to_next} zebranych do awansu"
+            = t('.gap', count: rung.gap_to_next)
 
         %li.gh-rank-row
           = render 'rank_thumb', rank: rung.rank
@@ -27,26 +25,24 @@
             - required_by = ladder.dependent_items(rung.rank)
             - if required_by.any?
               %small.gh-rank-row-requirement
-                = "Wymagana do zakupu: #{required_by.map(&:name).join(', ')}"
+                = t('.required_by', items: required_by.map(&:name).join(', '))
 
           .gh-rank-row-stats
             %b= rung.holders
-            = gh_plural(rung.holders, 'student', 'studentów', 'studentów')
+            = t('.holders', count: rung.holders)
             - if ladder.total_students.positive?
               .gh-progress-bar.gh-octagon-clip{ role: 'progressbar',
                        'aria-valuemin': 0,
                        'aria-valuemax': ladder.total_students,
                        'aria-valuenow': rung.holders,
-                       'aria-label': "Studenci z rangą #{rung.rank.name}" }
+                       'aria-label': t('.progress_label', name: rung.rank.name) }
                 %i.gh-octagon-clip{ style: "--gh-p: #{gh_percent(rung.holders, ladder.total_students)}%" }
 
           = link_to edit_story_group_rank_path(@story_group, rung.rank),
             class: 'gh-btn gh-btn--secondary gh-btn--small' do
             %i.fa-solid.fa-pen
-            Edytuj
+            = t('shared.actions.edit')
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Nie ma jeszcze żadnych rang
-    %p.gh-lead
-      Dodaj rangi, żeby studenci widzieli, do czego dążą. Ranga zależy od łącznie
-      zebranej waluty, a każda może dawać zniżkę w sklepie.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/ranks/confirm_destroy.html.haml b/app/views/ranks/confirm_destroy.html.haml
index ed89b182..abcd9cd8 100644
--- a/app/views/ranks/confirm_destroy.html.haml
+++ b/app/views/ranks/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń rangę #{@rank.name}"
+- content_for :title, t('.page_title', name: @rank.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/ranks/edit.html.haml b/app/views/ranks/edit.html.haml
index c3f29608..53ac8cec 100644
--- a/app/views/ranks/edit.html.haml
+++ b/app/views/ranks/edit.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, "Edytuj rangę - #{@rank.name}"
+- content_for :title, t('.page_title', name: @rank.name)
 
 = render 'form', rank: @rank, ladder: @ladder
diff --git a/app/views/ranks/index.html.haml b/app/views/ranks/index.html.haml
index d07fe499..83478dba 100644
--- a/app/views/ranks/index.html.haml
+++ b/app/views/ranks/index.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Rangi'
+- content_for :title, t('.title')
 
 - if @ladder.membership
   = render 'student_ladder', ladder: @ladder
diff --git a/app/views/ranks/new.html.haml b/app/views/ranks/new.html.haml
index 617e052f..37ce92ec 100644
--- a/app/views/ranks/new.html.haml
+++ b/app/views/ranks/new.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, 'Nowa ranga'
+- content_for :title, t('.page_title')
 
 = render 'form', rank: @rank, ladder: @ladder
diff --git a/app/views/sessions/new.html.haml b/app/views/sessions/new.html.haml
index 86cac741..e9cc69ea 100644
--- a/app/views/sessions/new.html.haml
+++ b/app/views/sessions/new.html.haml
@@ -1,19 +1,19 @@
-- content_for :title, 'Zaloguj się'
+- content_for :title, t('.title')
 
-%h1.gh-h1 Zaloguj się
-%p.gh-lead Wybierz sposób, z którego korzystasz na swojej uczelni lub w szkole.
+%h1.gh-h1= t('.title')
+%p.gh-lead= t('.lead')
 
 .gh-button-stack
   = button_to '/auth/uam_usos', class: 'gh-btn', data: { turbo: false } do
     %i.fa-solid.fa-graduation-cap
-    Zaloguj się przez USOS
-  %p.gh-signed-in-as Studenci i nauczyciele uczelni
+    = t('.usos')
+  %p.gh-signed-in-as= t('.usos_hint')
 
-  .gh-auth-divider albo
+  .gh-auth-divider= t('.or')
 
   = link_to new_auth_passwordless_path, class: 'gh-btn gh-btn--secondary' do
     %i.fa-solid.fa-envelope
-    Zaloguj się e-mailem
-  %p.gh-signed-in-as Uczniowie szkół i osoby dodane przez administratora
+    = t('.email')
+  %p.gh-signed-in-as= t('.email_hint')
 
 = render 'shared/register_prompt'
diff --git a/app/views/shared/_category_row.html.haml b/app/views/shared/_category_row.html.haml
index 217e065a..7704cdee 100644
--- a/app/views/shared/_category_row.html.haml
+++ b/app/views/shared/_category_row.html.haml
@@ -7,14 +7,14 @@
             data: { sheet_form_target: 'row', gh_locked: locked.to_s } }
   = f.hidden_field :position, data: { sheet_form_target: 'position' }
 
-  %span.gh-category-drag-handle{ title: 'Przeciągnij, aby zmienić kolejność', 'aria-hidden': 'true' }
+  %span.gh-category-drag-handle{ title: t('.drag'), 'aria-hidden': 'true' }
     %i.fa-solid.fa-grip-vertical
 
   .gh-category-row-body
     .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:didactic_description)) }
       = f.text_field :didactic_description, autocomplete: 'off',
-        placeholder: 'Za co, np. Pomoc innym',
-        'aria-label': "Kategoria #{number}: za co",
+        placeholder: t('.name_placeholder'),
+        'aria-label': t('shared.sheet_form.js.name_label', number: number),
         'aria-invalid': (error.call(:didactic_description) ? 'true' : nil),
         data: { sheet_form_target: 'name', action: 'sheet-form#refresh' }
     - if error.call(:didactic_description)
@@ -25,33 +25,32 @@
     %details.gh-story-disclosure{ open: category.story_description.present? }
       %summary.gh-category-story-toggle.gh-link-button
         %i.fa-solid.fa-align-left{ 'aria-hidden': 'true' }
-        Dodaj opis fabularny
+        = t('.add_story')
       .gh-text-input.gh-category-story-textarea
         = f.text_area :story_description, rows: 1,
-          placeholder: 'Opis fabularny, np. Holowanie uszkodzonego statku',
-          'aria-label': "Opis fabularny kategorii #{number}"
+          placeholder: t('.story_placeholder'),
+          'aria-label': t('shared.sheet_form.js.story_label', number: number)
 
     - if sheet && category.persisted? && category.sheet_only?
-      %span.gh-tag.gh-tag--sheet-only Tylko w tym arkuszu
+      %span.gh-tag.gh-tag--sheet-only= t('.sheet_only')
     - if sheet
       %span.gh-tag.gh-tag--hidden-column{ hidden: !category.hidden?,
                                    data: { sheet_form_target: 'hiddenTag' } }
-        Ukryta w tabeli ocen
+        = t('.hidden_column')
 
     - if locked
-      - awards = category.awards_count
       %p.gh-category-lock-note
         %i.fa-solid.fa-lock{ 'aria-hidden': 'true' }
         %span
-          = "Przyznano #{awards} #{gh_plural(awards, 'nagrodę', 'nagrody', 'nagród')}."
-          Kolumny nie można usunąć, można ją ukryć.
+          = t('.awarded', count: category.awards_count)
+          = t('.locked_note')
           %span{ hidden: (category.reward == category.reward_was), data: { sheet_form_target: 'rewardNote' } }
-            Nowa wartość obejmie tylko przyszłe nagrody.
+            = t('.reward_note')
 
   .gh-category-row-price
     .gh-text-input.gh-text-input--numeric{ class: ('gh-text-input--invalid' if error.call(:reward)) }
       = f.number_field :reward, min: 1, step: 1,
-        'aria-label': "Nagroda za kategorię #{number}",
+        'aria-label': t('shared.sheet_form.js.reward_label', number: number),
         'aria-invalid': (error.call(:reward) ? 'true' : nil),
         data: { sheet_form_target: 'reward', action: 'sheet-form#refresh',
                 gh_awarded: (locked ? category.reward_was : nil) }
@@ -62,21 +61,23 @@
         %span= error.call(:reward)
 
   .gh-category-row-actions
-    %button.gh-icon-button{ type: 'button', 'aria-label': 'Przesuń wyżej',
+    %button.gh-icon-button{ type: 'button', 'aria-label': t('.move_up'),
                         data: { action: 'sheet-form#moveUp', sheet_form_target: 'up' } }
       %i.fa-solid.fa-chevron-up{ 'aria-hidden': 'true' }
-    %button.gh-icon-button{ type: 'button', 'aria-label': 'Przesuń niżej',
+    %button.gh-icon-button{ type: 'button', 'aria-label': t('.move_down'),
                         data: { action: 'sheet-form#moveDown', sheet_form_target: 'down' } }
       %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
     - if locked
-      %label.gh-icon-button.gh-icon-toggle{ title: (category.hidden? ? 'Pokaż' : 'Ukryj') + ' w tabeli ocen' }
+      - toggle = category.hidden? ? t('.show') : t('.hide')
+      %label.gh-icon-button.gh-icon-toggle{ title: toggle }
         = f.check_box :hidden, { data: { sheet_form_target: 'hide', action: 'sheet-form#refresh' },
-                                 'aria-label': (category.hidden? ? 'Pokaż w tabeli ocen' : 'Ukryj w tabeli ocen') }
+                                 'aria-label': toggle }
         %i.fa-solid{ class: (category.hidden? ? 'fa-eye' : 'fa-eye-slash'), 'aria-hidden': 'true',
                      data: { sheet_form_target: 'hideIcon' } }
     - else
-      %label.gh-icon-button.gh-icon-toggle{ title: 'Usuń' }
+      %label.gh-icon-button.gh-icon-toggle{ title: t('shared.actions.remove') }
         = f.check_box :_destroy, { data: { sheet_form_target: 'destroy', action: 'sheet-form#remove' },
-                                   'aria-label': "Usuń kategorię #{number}" }
+                                   'aria-label': t(sheet ? 'shared.sheet_form.js.destroy_column' : 'shared.sheet_form.js.destroy_category',
+                                                             number: number) }
         %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
diff --git a/app/views/shared/_grid_preview.html.haml b/app/views/shared/_grid_preview.html.haml
index eddd20e6..55fb42dc 100644
--- a/app/views/shared/_grid_preview.html.haml
+++ b/app/views/shared/_grid_preview.html.haml
@@ -1,18 +1,18 @@
-- sample = local_assigns[:sample_names].presence || ['Adam Pawłowski', 'Barbara Kowalewska']
+- sample = local_assigns[:sample_names].presence || t('shared.sheet_form.sample_names')
 
 %details.gh-preview-details{ open: true }
   %summary
-    Podgląd tabeli ocen
+    = t('.summary')
     %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
   %section.gh-panel.gh-preview-panel
-    %h3.gh-h3 Nagłówek tabeli ocen
+    %h3.gh-h3= t('.header')
 
     .gh-grading-table-preview
       %table.gh-grading-table
         %thead
           %tr{ data: { sheet_form_target: 'previewHead' } }
-            %th.gh-grading-th-student{ scope: 'col' } Student
+            %th.gh-grading-th-student{ scope: 'col' }= t('.student')
             - categories.each do |category|
               %th{ scope: 'col' }
                 .gh-grading-column-head
@@ -28,7 +28,7 @@
                 %td
                   %span.gh-grading-cell.gh-grading-cell--sm
 
-    %span.gh-field-hint Najedź na nagłówek w prawdziwej tabeli, żeby zobaczyć opis fabularny.
+    %span.gh-field-hint= t('.hint')
 
 %template{ data: { sheet_form_target: 'previewHeadCell' } }
   %th{ scope: 'col' }
diff --git a/app/views/shared/_image_field.html.haml b/app/views/shared/_image_field.html.haml
index 3e0b3e25..8ff19dc1 100644
--- a/app/views/shared/_image_field.html.haml
+++ b/app/views/shared/_image_field.html.haml
@@ -2,13 +2,7 @@
 - glyph_attribute = local_assigns.fetch(:glyph_attribute, :icon_glyph)
 - registry        = local_assigns.fetch(:registry, Glyphs)
 - tile            = local_assigns.fetch(:tile, :glyph)
-- defaults        = { label: 'Grafika',
-                      presets: 'Gotowe grafiki',
-                      own: 'Twoja grafika',
-                      upload: 'Albo wgraj własną grafikę',
-                      hint: 'JPG lub PNG, najlepiej co najmniej 400 px.',
-                      crop: 'Przytnij grafikę',
-                      cropped: 'Przesuń i przeskaluj zaznaczenie — podgląd obok zmienia się na bieżąco. Zapisujemy kadr w kształcie karty, więc wypełni ją w całości. Na listach zobaczysz go w kwadratowej miniaturze, też w całości.', }
+- defaults        = t('shared.image_field').slice(:label, :presets, :own, :upload, :hint, :crop, :cropped)
 - copy            = defaults.merge(local_assigns.fetch(:copy, {}))
 
 - field_id  = ->(suffix) { "gh-#{kind}-art-#{suffix}" }
@@ -19,7 +13,8 @@
 
 .gh-form-field{ data: { controller: 'image-crop',
                  image_crop_aspect_value: local_assigns.fetch(:aspect, 1.6),
-                 image_crop_width_value: 1024, } }
+                 image_crop_width_value: 1024,
+                 image_crop_alt_value: copy[:own], } }
   %p.gh-form-label= copy[:label]
 
   .gh-art-preset-grid{ class: "gh-art-preset-grid--#{kind}", role: 'radiogroup', 'aria-label': copy[:presets],
@@ -29,7 +24,7 @@
       %label.gh-art-preset-tile{ class: "gh-art-preset-tile--#{kind}" }
         = form.radio_button glyph_attribute, key, class: 'sr-only',
           id: field_id.call(key),
-          'aria-label': "#{copy[:label]}: #{registry.label_for(key)}",
+          'aria-label': t('.preset_label', label: copy[:label], name: registry.label_for(key)),
           data: { action: ['image-crop#pickPreset', refresh].compact.join(' ') }
         %i.gh-octagon-clip
           - case tile
@@ -63,7 +58,7 @@
       %b= copy[:upload]
       %small= copy[:hint]
     %label.gh-btn.gh-btn--secondary.gh-btn--small
-      Wybierz plik
+      = t('.choose_file')
       = form.file_field attribute, class: 'sr-only',
         accept: 'image/png,image/jpeg,image/gif',
         data: { image_crop_target: 'input', action: 'image-crop#choose' }
diff --git a/app/views/shared/_invitation_email.html.haml b/app/views/shared/_invitation_email.html.haml
index 664ba2df..de93e341 100644
--- a/app/views/shared/_invitation_email.html.haml
+++ b/app/views/shared/_invitation_email.html.haml
@@ -9,20 +9,17 @@
           %td.gh-invitation-email-body
             %p.gh-invitation-email-brand Gamification Hub
 
-            %h1.gh-invitation-email-title Zaproszenie
+            %h1.gh-invitation-email-title= t('.title')
             %p.gh-invitation-email-lead= lead
-            %p.gh-invitation-email-text
-              Kliknij przycisk poniżej, aby dokończyć zakładanie konta i uzupełnić swoje dane.
+            %p.gh-invitation-email-text= t('.text')
 
             %table{ cellpadding: 0, cellspacing: 0, border: 0 }
               %tr
                 %td.gh-invitation-email-button{ align: 'center' }
-                  %a.gh-invitation-email-button-link{ href: token_link } Dokończ zakładanie konta
+                  %a.gh-invitation-email-button-link{ href: token_link }= t('.button')
 
-            %p.gh-invitation-email-note
-              Link jest ważny przez 7 dni. Jeśli przycisk nie działa, skopiuj ten adres do przeglądarki:
+            %p.gh-invitation-email-note= t('.note')
             %p.gh-invitation-email-url
               %a{ href: token_link }= token_link
 
-            %p.gh-invitation-email-footer
-              Jeśli nie spodziewałeś się tego zaproszenia, możesz zignorować tę wiadomość.
+            %p.gh-invitation-email-footer= t('.footer')
diff --git a/app/views/shared/_invitation_email.text.haml b/app/views/shared/_invitation_email.text.haml
index e9924020..d65a4526 100644
--- a/app/views/shared/_invitation_email.text.haml
+++ b/app/views/shared/_invitation_email.text.haml
@@ -2,10 +2,10 @@ Gamification Hub
 
 = lead
 
-Aby dokończyć zakładanie konta i uzupełnić swoje dane, otwórz poniższy link.
+= t('.text_plain')
 
 = token_link
 
-Link jest ważny przez 7 dni.
+= t('.valid_for')
 
-Jeśli nie spodziewałeś się tego zaproszenia, możesz zignorować tę wiadomość.
+= t('.footer')
diff --git a/app/views/shared/_register_prompt.html.haml b/app/views/shared/_register_prompt.html.haml
index 0d8c51e4..3398e57a 100644
--- a/app/views/shared/_register_prompt.html.haml
+++ b/app/views/shared/_register_prompt.html.haml
@@ -1,3 +1,3 @@
 %p.gh-auth-alt-action
-  Nie masz konta?
-  %button.gh-link-button{ type: 'button' } Zarejestruj się
+  = t('.no_account')
+  %button.gh-link-button{ type: 'button' }= t('.register')
diff --git a/app/views/shared/_sheet_form.html.haml b/app/views/shared/_sheet_form.html.haml
index 93abc57f..1ba6a2a5 100644
--- a/app/views/shared/_sheet_form.html.haml
+++ b/app/views/shared/_sheet_form.html.haml
@@ -8,29 +8,28 @@
 - sheet_names  = local_assigns[:sheet_names] || []
 - awards_count = local_assigns[:awards_count].to_i
 
-- sample_names = @story_group.student_memberships.with_user.first(2).map(&:display_name).presence || ['Adam Pawłowski', 'Barbara Kowalewska']
+- sample_names = @story_group.student_memberships.with_user.first(2).map(&:display_name).presence || t('.sample_names')
 
-- headings   = { template_new: 'Nowy szablon arkusza', template_edit: 'Edytuj szablon arkusza', sheet: 'Ustawienia arkusza' }
+- headings   = { template_new: t('.template_new_title'), template_edit: t('.template_edit_title'),
+                 sheet: t('.sheet_title') }
 - heading    = headings[variant]
 - crumb_tail = sheet ? record.name : (record.base_name_was.presence || record.base_name)
-- crumb_tail = 'Nowy szablon' if variant == :template_new
+- crumb_tail = t('.new_template') if variant == :template_new
 
 - form_data = { controller: 'sheet-form',
-                sheet_form_columns_value: %w[kolumna kolumny kolumn].to_json,
-                sheet_form_currency_value: @story_group.currency_name.to_s,
-                sheet_form_category_label_value: (sheet ? 'kolumnę' : 'kategorię'),
+                sheet_form_i18n_value: t('.js').to_json,
+                sheet_form_sheet_value: sheet,
                 sheet_form_editing_value: editing.to_s }
 
 %div{ data: form_data }
   %section.gh-panel.gh-page-header.gh-page-header--stacked
     %p.gh-breadcrumbs
-      = link_to 'Arkusze ocen', story_group_activity_groups_path(@story_group),
+      = link_to t('.breadcrumb'), story_group_activity_groups_path(@story_group),
         data: { action: 'sheet-form#leave' }
       %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
       %span= crumb_tail
     %h1.gh-h1= heading
-    %p.gh-lead
-      = sheet ? 'Zmiany dotyczą tylko tego arkusza.' : 'Podgląd obok pokazuje nagłówek tabeli ocen.'
+    %p.gh-lead= sheet ? t('.sheet_lead') : t('.template_lead')
 
   = form_with model: [@story_group, record], data: { sheet_form_target: 'form' } do |f|
     .gh-form-shell
@@ -39,18 +38,17 @@
           %p.gh-info-banner
             %i.fa-solid.fa-table{ 'aria-hidden': 'true' }
             %span
-              %b Zmiany dotyczą tylko arkuszy utworzonych od teraz.
+              %b= t('.template_changes')
               - if sheet_names.many?
-                = "#{sheet_names.first} – #{sheet_names.last} zostają bez zmian."
+                = t('.sheets_range_unchanged', first: sheet_names.first, last: sheet_names.last)
               - else
-                = "#{sheet_names.first} zostaje bez zmian."
+                = t('.sheet_unchanged', name: sheet_names.first)
         - if sheet && awards_count.positive?
           %p.gh-info-banner
             %i.fa-solid.fa-lock{ 'aria-hidden': 'true' }
             %span
-              %b= "W tym arkuszu przyznano już #{awards_count} #{gh_plural(awards_count, 'nagrodę', 'nagrody', 'nagród')}."
-              Zmiany kolumn dotyczą tylko przyszłych nagród.
-              = "Szablon #{record.activity_group_template.base_name} się nie zmienia."
+              %b= t('.awarded', count: awards_count)
+              = t('.awarded_note', name: record.activity_group_template.base_name)
 
         - if record.errors[:base].any?
           %p.gh-field-error{ role: 'alert' }
@@ -59,10 +57,10 @@
 
         .gh-form-section
           .gh-form-field.mt-0
-            = f.label name_attr, sheet ? 'Nazwa arkusza' : 'Nazwa szablonu'
+            = f.label name_attr, sheet ? t('.sheet_name') : t('.template_name')
             .gh-text-input{ class: ('gh-text-input--invalid' if error.call(name_attr)) }
               = f.text_field name_attr, maxlength: 100, autocomplete: 'off',
-                placeholder: (sheet ? 'np. Laboratoria 5 (14.10)' : 'np. Laboratoria'),
+                placeholder: (sheet ? t('.sheet_name_placeholder') : t('.template_name_placeholder')),
                 'aria-invalid': (error.call(name_attr) ? 'true' : nil),
                 'aria-describedby': (error.call(name_attr) ? 'gh-sheet-name-error' : nil),
                 data: { sheet_form_target: 'title', action: 'sheet-form#refresh' }
@@ -72,13 +70,11 @@
                 %span= error.call(name_attr)
             - unless sheet
               %span.gh-field-hint
-                Nowe arkusze dostaną nazwę szablonu z kolejnym numerem, np.
-                = "#{record.base_name.presence || 'Laboratoria'} 6."
+                = t('.template_name_hint', example: record.base_name.presence || t('.name_example'))
 
         .gh-form-section
-          %h2.gh-h3= sheet ? 'Kolumny w tabeli ocen' : 'Kategorie nagród'
-          %p.gh-field-hint
-            Każda kategoria to kolumna w tabeli ocen. Kolejność tutaj to kolejność kolumn.
+          %h2.gh-h3= sheet ? t('.sheet_columns') : t('.template_categories')
+          %p.gh-field-hint= t('.columns_hint')
 
           %ul.gh-category-list{ data: { controller: 'sortable-rows', sheet_form_target: 'list',
                                action: 'sortable-rows:reordered->sheet-form#refresh' } }
@@ -88,14 +84,15 @@
 
           %button.gh-btn.gh-btn--secondary.gh-add-category-btn{ type: 'button', data: { action: 'sheet-form#add' } }
             %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-            = sheet ? 'Dodaj kolumnę' : 'Dodaj kategorię'
+            = sheet ? t('.add_column') : t('.add_category')
 
           %p.gh-explainer-note
-            %span{ data: { sheet_form_target: 'summaryCount' } }
-              = "#{visible.size} #{gh_plural(visible.size, 'kolumna', 'kolumny', 'kolumn')}"
-            w tabeli ocen. Student może zdobyć do
-            %b{ data: { sheet_form_target: 'summaryMax' } }= visible.sum { |category| category.reward.to_i }
-            = "#{@story_group.currency_name} za arkusz."
+            = gh_fill(t('.summary'),
+                      count:    tag.span(t('.js.columns', count: visible.size),
+                                         data: { sheet_form_target: 'summaryCount' }),
+                      max:      tag.b(visible.sum { |category| category.reward.to_i },
+                                      data: { sheet_form_target: 'summaryMax' }),
+                      currency: @story_group.currency_name)
 
           %template{ data: { sheet_form_target: 'blank' } }
             = f.fields_for cats_attr, categories.klass.new(reward: 1), child_index: 'NEW_RECORD' do |cf|
@@ -104,35 +101,34 @@
 
         - if editing
           .gh-form-section
-            %h2.gh-h3 Usuwanie
-            %p.gh-field-hint
-              = sheet ? 'Arkusz zniknie z listy, a przyznane nagrody zostają u studentów i w ich historii.' : 'Szablon zniknie z listy, a utworzone z niego arkusze zostają.'
+            %h2.gh-h3= t('shared.actions.removal')
+            %p.gh-field-hint= sheet ? t('.sheet_removal_hint') : t('.template_removal_hint')
             .gh-button-row
               - path = sheet ? confirm_destroy_story_group_activity_group_path(@story_group, record) : confirm_destroy_story_group_activity_group_template_path(@story_group, record)
               = link_to path, class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
                 %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-                = sheet ? 'Usuń arkusz' : 'Usuń szablon'
+                = sheet ? t('.remove_sheet') : t('.remove_template')
 
-      %aside.gh-preview-column{ 'aria-label': 'Podgląd' }
+      %aside.gh-preview-column{ 'aria-label': t('shared.actions.preview') }
         = render 'shared/grid_preview', categories: visible, sample_names: sample_names
 
     .gh-panel.gh-form-actions-bar
-      = link_to 'Anuluj', story_group_activity_groups_path(@story_group), class: 'gh-link-button',
+      = link_to t('shared.actions.cancel'), story_group_activity_groups_path(@story_group), class: 'gh-link-button',
         data: { action: 'sheet-form#leave' }
       %span.gh-form-actions-spacer
       - if editing
-        %span.gh-small{ data: { sheet_form_target: 'dirty' } } Brak zmian
+        %span.gh-small{ data: { sheet_form_target: 'dirty' } }= t('.no_changes')
       %button.gh-btn{ type: 'submit', data: { sheet_form_target: 'submit' } }
         - unless editing
           %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-        = editing ? 'Zapisz zmiany' : 'Utwórz szablon'
+        = editing ? t('shared.actions.save_changes') : t('.create')
 
   %dialog.gh-dialog{ data: { sheet_form_target: 'discard',
                              action: 'close->sheet-form#closeDiscard click->sheet-form#closeOnBackdrop' } }
     .gh-dialog-body.gh-octagon-clip
-      %h2.gh-h2 Odrzucić zmiany?
-      %p Niezapisane zmiany zostaną utracone.
+      %h2.gh-h2= t('.discard_title')
+      %p= t('.discard_body')
       .gh-dialog-button-row
         %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'sheet-form#closeDiscard' }, autofocus: true }
-          Wróć do edycji
-        %button.gh-btn{ type: 'button', data: { action: 'sheet-form#discard' } } Odrzuć zmiany
+          = t('shared.actions.back_to_editing')
+        %button.gh-btn{ type: 'button', data: { action: 'sheet-form#discard' } }= t('.discard')
diff --git a/app/views/shop/_buy_button.html.haml b/app/views/shop/_buy_button.html.haml
index 7ab73449..9b2dec04 100644
--- a/app/views/shop/_buy_button.html.haml
+++ b/app/views/shop/_buy_button.html.haml
@@ -1,4 +1,4 @@
 = link_to confirm_buy_story_group_shop_path(@story_group, item),
   class: 'gh-btn', data: { turbo_frame: 'modal' },
-  'aria-label': "Kup #{item.name} za #{price}" do
-  = "Kup za #{price}"
+  'aria-label': t('.label', name: item.name, price: price) do
+  = t('.buy', price: price)
diff --git a/app/views/shop/_confirm_buy.html.haml b/app/views/shop/_confirm_buy.html.haml
index 07010e07..1e98e1ff 100644
--- a/app/views/shop/_confirm_buy.html.haml
+++ b/app/views/shop/_confirm_buy.html.haml
@@ -1,36 +1,36 @@
 - price = offer.price
 - left  = @student.current_currency.to_i - price
 
-%h2#gh-buy-title.gh-h2= "Kupić „#{item.name}”?"
+%h2#gh-buy-title.gh-h2= t('.title', name: item.name)
 
 .gh-purchase-summary
   = render 'layouts/item_thumb', item: item
   %dl.gh-purchase-details
-    %dt Cena
+    %dt= t('.price')
     %dd
       - if offer.discounted?
         %s= offer.list_price
       %span.gh-buy-v= price
       = render 'layouts/currency_token', story_group: @story_group, size: 22
-    %dt Zostanie Ci
+    %dt= t('.left')
     %dd
       %span.gh-buy-v= left
       = render 'layouts/currency_token', story_group: @story_group, size: 22
 
 - if offer.discounted?
-  %p.gh-small.gh-note-row= "Zniżka #{offer.discount_label}."
+  %p.gh-small.gh-note-row= t('.discount', label: offer.discount_label)
 
 %p.gh-small.gh-note-row
   %i.fa-solid.fa-bell{ 'aria-hidden': 'true' }
-  %span Prowadzący dostanie powiadomienie o zakupie.
+  %span= t('.notice')
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', story_group_shop_index_path(@story_group), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), story_group_shop_index_path(@story_group), class: 'gh-btn gh-btn--secondary'
 
-  = button_to "Kup za #{price}", buy_story_group_shop_path(@story_group, item),
+  = button_to t('.buy', price: price), buy_story_group_shop_path(@story_group, item),
     method: :post, class: 'gh-btn',
     form: { data: { turbo_frame: '_top' } }
diff --git a/app/views/shop/confirm_buy.html.haml b/app/views/shop/confirm_buy.html.haml
index c7df3eca..7203ad10 100644
--- a/app/views/shop/confirm_buy.html.haml
+++ b/app/views/shop/confirm_buy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Kup #{@item.name}"
+- content_for :title, t('.page_title', name: @item.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/shop/index.html.haml b/app/views/shop/index.html.haml
index 741ddb94..fa65772b 100644
--- a/app/views/shop/index.html.haml
+++ b/app/views/shop/index.html.haml
@@ -1,8 +1,8 @@
-- content_for :title, 'Sklep'
+- content_for :title, t('.title')
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Sklep
+    %h1.gh-h1= t('.title')
     %p.gh-lead
       = shop_balance_sentence(@shop.balance)
       = shop_discount_sentence(@shop.discount_badges)
@@ -11,11 +11,11 @@
     = render 'layouts/currency_token', story_group: @story_group, size: 32
     %div
       %b= @shop.balance
-      %small do wydania
+      %small= t('.to_spend')
     %span.gh-wallet-divider{ 'aria-hidden': 'true' }
     %div
       %b= @shop.total
-      %small zebrane łącznie
+      %small= t('.collected')
 
 - if @shop.any?
   - @shop.zones.each do |zone|
@@ -28,7 +28,5 @@
           = render 'shop/card', offer: offer, state: zone.key
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Sklep jest jeszcze pusty
-    %p.gh-lead
-      Prowadzący nie dodał jeszcze przedmiotów. Zbieraj walutę — przyda się,
-      kiedy sklep się otworzy.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
diff --git a/app/views/story_group_invites/_cancel.html.haml b/app/views/story_group_invites/_cancel.html.haml
index cb598c7e..0dc8c08a 100644
--- a/app/views/story_group_invites/_cancel.html.haml
+++ b/app/views/story_group_invites/_cancel.html.haml
@@ -1,4 +1,4 @@
 - if @in_modal
-  %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+  %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
 - else
-  = link_to 'Anuluj', story_group_invites_path(@story_group), class: 'gh-btn gh-btn--secondary'
+  = link_to t('shared.actions.cancel'), story_group_invites_path(@story_group), class: 'gh-btn gh-btn--secondary'
diff --git a/app/views/story_group_invites/_code.html.haml b/app/views/story_group_invites/_code.html.haml
index 7dbe13a9..3a34da84 100644
--- a/app/views/story_group_invites/_code.html.haml
+++ b/app/views/story_group_invites/_code.html.haml
@@ -1,10 +1,10 @@
-%h2#gh-code-title.gh-h2= "Dołącz do grupy #{@story_group.name}"
-%p Wpisz kod w aplikacji („Dołącz do grupy”) albo zeskanuj kod QR.
+%h2#gh-code-title.gh-h2= t('.title', name: @story_group.name)
+%p= t('.hint')
 
 = render 'qr_stat', invite: invite
 
 .gh-dialog-button-row
   - if @in_modal
-    %button.gh-btn{ type: 'button', data: { action: 'dialog#close' }, autofocus: true } Zamknij
+    %button.gh-btn{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }= t('shared.actions.close')
   - else
-    = link_to 'Zamknij', story_group_invites_path(@story_group), class: 'gh-btn'
+    = link_to t('shared.actions.close'), story_group_invites_path(@story_group), class: 'gh-btn'
diff --git a/app/views/story_group_invites/_confirm_destroy.html.haml b/app/views/story_group_invites/_confirm_destroy.html.haml
index c73c2be2..87ea690c 100644
--- a/app/views/story_group_invites/_confirm_destroy.html.haml
+++ b/app/views/story_group_invites/_confirm_destroy.html.haml
@@ -1,18 +1,17 @@
 - joined = invite.uses.to_i
 
-%h2#gh-del-title.gh-h2= "Usunąć zaproszenie #{invite.code}?"
+%h2#gh-del-title.gh-h2= t('.title', code: invite.code)
 %p
-  Kod przestanie działać od razu.
+  = t('.body')
   - if joined.positive?
-    = "#{joined} #{gh_plural(joined, 'osoba, która dołączyła', 'osoby, które dołączyły', 'osób, które dołączyły')}"
-    = 'z tym kodem, zostaje w grupie.'
+    = t('.joined', count: joined)
 
 .gh-dialog-button-row
   - if @in_modal
-    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true } Anuluj
+    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }= t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', story_group_invites_path(@story_group), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), story_group_invites_path(@story_group), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń zaproszenie', story_group_invite_path(@story_group, invite),
+  = button_to t('.remove'), story_group_invite_path(@story_group, invite),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/story_group_invites/_copy_button.html.haml b/app/views/story_group_invites/_copy_button.html.haml
index 2c42f4d4..91a5d1c4 100644
--- a/app/views/story_group_invites/_copy_button.html.haml
+++ b/app/views/story_group_invites/_copy_button.html.haml
@@ -1,5 +1,5 @@
 - labelled = local_assigns.fetch(:labelled, true)
-- title = "Kopiuj kod #{invite.code}"
+- title = t('.title', code: invite.code)
 
 %button{ type: 'button',
          class: labelled ? 'gh-btn gh-btn--secondary gh-copy-action' : 'gh-icon-button',
@@ -9,8 +9,8 @@
                  action: 'clipboard#copy',
                  clipboard_title: title,
                  clipboard_text_value: invite.code,
-                 clipboard_done_value: 'Skopiowano',
-                 clipboard_message_value: "Skopiowano kod #{invite.code}." } }
+                 clipboard_done_value: t('.done'),
+                 clipboard_message_value: t('.message', code: invite.code) } }
   %i.fa-solid.fa-copy{ 'aria-hidden': 'true', data: { clipboard_target: 'icon' } }
   - if labelled
-    %span{ data: { clipboard_target: 'label' } } Kopiuj kod
+    %span{ data: { clipboard_target: 'label' } }= t('.label')
diff --git a/app/views/story_group_invites/_form.html.haml b/app/views/story_group_invites/_form.html.haml
index 499dfa19..c2f1b6ca 100644
--- a/app/views/story_group_invites/_form.html.haml
+++ b/app/views/story_group_invites/_form.html.haml
@@ -5,33 +5,23 @@
 - scope = ->(field) { "story_group_invite[#{field}]" }
 
 %h2#gh-invite-title.gh-h2
-  = editing ? "Edytuj zaproszenie #{invite.code}" : 'Nowe zaproszenie'
-%p
-  - if editing
-    Kod zostaje ten sam. Zmieniasz tylko ograniczenia.
-  - else
-    Oba ograniczenia są opcjonalne.
+  = editing ? t('.edit_title', code: invite.code) : t('.new_title')
+%p= editing ? t('.edit_hint') : t('.new_hint')
 
 = form_with url: (editing ? story_group_invite_path(@story_group, invite) : story_group_invites_path(@story_group)),
   method: (editing ? :patch : :post),
   data: { controller: 'invite-form',
           turbo_frame: (@in_modal ? 'modal' : nil),
-          invite_form_summary_prefix_value: 'Kod będzie działał',
-          invite_form_limit_prefix_value: 'dla',
-          invite_form_no_limit_value: 'bez limitu osób',
-          invite_form_expiry_prefix_value: 'do',
-          invite_form_no_expiry_value: 'i bez daty ważności',
-          invite_form_people_forms_value: %w[osoby osób osób].to_json,
-          invite_form_unit_forms_value: %w[osoba osoby osób].to_json } do
+          invite_form_i18n_value: invite_form_wording.to_json } do
 
   - unless editing
     .gh-invite-presets
       %button.gh-purchase-filter-chip{ type: 'button',
                         data: { preset: 'today', action: 'invite-form#preset' } }
-        Na dzisiejsze zajęcia
+        = t('.today')
       %button.gh-purchase-filter-chip{ type: 'button',
                         data: { preset: 'none', action: 'invite-form#preset' } }
-        Bez ograniczeń
+        = t('.no_limits')
 
   .gh-invite-limits
     .gh-toggle-switch-row
@@ -41,13 +31,13 @@
         data: { invite_form_target: 'limitSwitch', action: 'invite-form#refresh' }
       %span
         %b
-          = label_tag 'gh-limit-switch', 'Limit użyć'
-        %span.gh-field-hint Kod przestanie działać, gdy dołączy tyle osób.
+          = label_tag 'gh-limit-switch', t('.limit')
+        %span.gh-field-hint= t('.limit_hint')
 
     .gh-limit-fields-row
       .gh-text-input.gh-text-input--numeric{ class: ('gh-text-input--invalid' if limit_error) }
         = number_field_tag scope.call(:max_uses), form.max_uses, min: 1, step: 1,
-          id: 'gh-max-uses', 'aria-label': 'Limit użyć',
+          id: 'gh-max-uses', 'aria-label': t('.limit'),
           'aria-invalid': limit_error ? 'true' : nil,
           'aria-describedby': (limit_error ? 'gh-limit-error' : nil),
           data: { invite_form_target: 'maxUses', action: 'invite-form#refresh' }
@@ -66,20 +56,20 @@
         data: { invite_form_target: 'expirySwitch', action: 'invite-form#refresh' }
       %span
         %b
-          = label_tag 'gh-expiry-switch', 'Data ważności'
-        %span.gh-field-hint Po tej chwili kod przestanie działać.
+          = label_tag 'gh-expiry-switch', t('.expiry')
+        %span.gh-field-hint= t('.expiry_hint')
 
     .gh-limit-fields-row
       .gh-text-input{ class: ('gh-text-input--invalid' if expiry_error) }
         = date_field_tag scope.call(:expires_on), form.expires_on,
-          id: 'gh-expires-on', 'aria-label': 'Data',
+          id: 'gh-expires-on', 'aria-label': t('.date'),
           'aria-invalid': expiry_error ? 'true' : nil,
           'aria-describedby': (expiry_error ? 'gh-expiry-error' : nil),
           data: { invite_form_target: 'date', today: Time.zone.today.to_fs(:iso8601),
                   action: 'invite-form#refresh' }
       .gh-text-input
         = time_field_tag scope.call(:expires_time), form.expires_time,
-          id: 'gh-expires-time', 'aria-label': 'Godzina',
+          id: 'gh-expires-time', 'aria-label': t('.time'),
           data: { invite_form_target: 'time', end_of_day: InviteForm::DEFAULT_TIME,
                   action: 'invite-form#refresh' }
 
@@ -92,4 +82,4 @@
 
   .gh-dialog-button-row
     = render 'cancel'
-    %button.gh-btn{ type: 'submit' }= editing ? 'Zapisz zmiany' : 'Utwórz zaproszenie'
+    %button.gh-btn{ type: 'submit' }= editing ? t('shared.actions.save_changes') : t('.create')
diff --git a/app/views/story_group_invites/_invite_row.html.haml b/app/views/story_group_invites/_invite_row.html.haml
index 6d0fdf5e..015a8508 100644
--- a/app/views/story_group_invites/_invite_row.html.haml
+++ b/app/views/story_group_invites/_invite_row.html.haml
@@ -7,13 +7,13 @@
     %span.gh-pill.gh-octagon-clip{ class: invite.active? ? 'gh-pill--earn' : 'gh-pill--corr' }= invite.status_label
 
   %span.gh-invite-usage
-    = "Użycia: #{invite_uses_label(invite)}"
+    = t('.uses', uses: invite_uses_label(invite))
     - if invite.max_uses
       .gh-progress-bar.gh-octagon-clip{ role: 'progressbar',
                'aria-valuemin': 0,
                'aria-valuemax': invite.max_uses,
                'aria-valuenow': invite.uses,
-               'aria-label': "Wykorzystanie kodu #{invite.code}" }
+               'aria-label': t('.usage_label', code: invite.code) }
         %i.gh-octagon-clip{ style: "--gh-p: #{gh_percent(invite.uses, invite.max_uses)}%" }
 
   %span.gh-invite-expiry= invite_expiry_label(invite)
@@ -23,16 +23,16 @@
       = link_to story_group_invite_path(@story_group, invite), class: 'gh-btn gh-btn--small',
         data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-qrcode
-        Pokaż
+        = t('.show')
 
     = render 'copy_button', invite: invite, labelled: false
 
     = link_to edit_story_group_invite_path(@story_group, invite), class: 'gh-icon-button',
-      title: 'Edytuj', 'aria-label': "Edytuj zaproszenie #{invite.code}",
+      title: t('shared.actions.edit'), 'aria-label': t('.edit_label', code: invite.code),
       data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-pen
 
     = link_to confirm_destroy_story_group_invite_path(@story_group, invite), class: 'gh-icon-button',
-      title: 'Usuń', 'aria-label': "Usuń zaproszenie #{invite.code}",
+      title: t('.remove'), 'aria-label': t('.remove_label', code: invite.code),
       data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-trash
diff --git a/app/views/story_group_invites/_quick.html.haml b/app/views/story_group_invites/_quick.html.haml
index d5c1a2b7..9db03f63 100644
--- a/app/views/story_group_invites/_quick.html.haml
+++ b/app/views/story_group_invites/_quick.html.haml
@@ -1,10 +1,10 @@
-%h2.gh-h2#gh-quick-title= "Dołącz do grupy #{@story_group.name}"
-%p Wpisz kod w aplikacji („Dołącz do grupy”) albo zeskanuj kod QR.
+%h2.gh-h2#gh-quick-title= t('.title', name: @story_group.name)
+%p= t('.hint')
 
 - if active.any?
   .gh-form-field{ data: { controller: 'invite-picker' } }
     %label{ for: 'gh-quick-select' }
-      = "Zaproszenie (aktywne: #{active.size}, najnowsze na górze)"
+      = t('.picker', count: active.size)
     %span.gh-select-input
       %select#gh-quick-select{data: { invite_picker_target: 'select',
                                       action:               'change->invite-picker#pick', }}
@@ -12,26 +12,24 @@
           %option{ value: invite.id }= invite_option_label(invite)
       %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
 
-    %p.gh-small
-      Wygasłe i wyczerpane zaproszenia są ukryte. Wszystkie znajdziesz w
-      zakładce Zaproszenia.
+    %p.gh-small= t('.hidden_note')
 
     - active.each_with_index do |invite, index|
       .gh-quick-block{hidden: index.positive?,
                       data:   { invite_picker_target: 'block', invite_picker_for: invite.id },}
         = render 'qr_stat', invite: invite
 - else
-  %p.gh-explainer-note Brak aktywnych zaproszeń. Utwórz nowe, żeby studenci mogli dołączyć.
+  %p.gh-explainer-note= t('.empty')
   .gh-button-row.gh-quick-invite-cta
     = link_to new_story_group_invite_path(@story_group), class: 'gh-btn',
                                                          data:  { turbo_frame: 'modal' } do
       %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      Nowe zaproszenie
+      = t('.new')
 
 .gh-dialog-button-row
-  = link_to 'Zarządzaj zaproszeniami', story_group_invites_path(@story_group),
+  = link_to t('.manage'), story_group_invites_path(@story_group),
             class: 'gh-btn gh-btn--secondary', data: { turbo_frame: '_top' }
   - if @in_modal
-    %button.gh-btn{ type: 'button', data: { action: 'dialog#close' }, autofocus: true } Zamknij
+    %button.gh-btn{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }= t('shared.actions.close')
   - else
-    = link_to 'Zamknij', story_group_invites_path(@story_group), class: 'gh-btn'
+    = link_to t('shared.actions.close'), story_group_invites_path(@story_group), class: 'gh-btn'
diff --git a/app/views/story_group_invites/confirm_destroy.html.haml b/app/views/story_group_invites/confirm_destroy.html.haml
index c2ec927b..8a0edee8 100644
--- a/app/views/story_group_invites/confirm_destroy.html.haml
+++ b/app/views/story_group_invites/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usunąć zaproszenie #{@invite.code}?"
+- content_for :title, t('.page_title', code: @invite.code)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_group_invites/edit.html.haml b/app/views/story_group_invites/edit.html.haml
index a3598911..7a98ee3b 100644
--- a/app/views/story_group_invites/edit.html.haml
+++ b/app/views/story_group_invites/edit.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Edytuj zaproszenie #{@invite.code}"
+- content_for :title, t('.page_title', code: @invite.code)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_group_invites/index.html.haml b/app/views/story_group_invites/index.html.haml
index 3f2b6dc1..5f4113a2 100644
--- a/app/views/story_group_invites/index.html.haml
+++ b/app/views/story_group_invites/index.html.haml
@@ -1,33 +1,31 @@
-- content_for :title, 'Zaproszenia'
+- content_for :title, t('.title')
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Zaproszenia
-    %p.gh-lead
-      Kod ma 6 znaków bez mylących liter (bez O, 0, I, 1 i L).
-      Studenci wpisują go w „Dołącz do grupy” albo skanują kod QR.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead')
 
   = link_to new_story_group_invite_path(@story_group), class: 'gh-btn',
     data: { turbo_frame: 'modal' } do
     %i.fa-solid.fa-plus
-    Nowe zaproszenie
+    = t('.new')
 
 %section.gh-panel.gh-invite-list
   .gh-invite-row.gh-invite-row--header{ 'aria-hidden': 'true' }
-    %span Kod
-    %span Status
-    %span Użycia
-    %span Ważność
+    %span= t('.code')
+    %span= t('.status')
+    %span= t('.uses')
+    %span= t('.validity')
     %span
 
   - if @active.any?
     = render partial: 'invite_row', collection: @active, as: :invite,
       locals: { fresh_id: @fresh_invite_id }
   - else
-    %p.gh-explainer-note Brak aktywnych zaproszeń. Utwórz nowe, żeby studenci mogli dołączyć.
+    %p.gh-explainer-note= t('.empty')
 
 - if @inactive.any?
   %details.gh-inactive-invites
-    %summary= "Nieaktywne (#{@inactive.size}): wygasłe i wyczerpane"
+    %summary= t('.inactive', count: @inactive.size)
     %section.gh-panel.gh-invite-list
       = render partial: 'invite_row', collection: @inactive, as: :invite
diff --git a/app/views/story_group_invites/new.html.haml b/app/views/story_group_invites/new.html.haml
index 21a4baa9..e82515e4 100644
--- a/app/views/story_group_invites/new.html.haml
+++ b/app/views/story_group_invites/new.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Nowe zaproszenie'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_group_invites/quick.html.haml b/app/views/story_group_invites/quick.html.haml
index 4c9a25fa..6327f720 100644
--- a/app/views/story_group_invites/quick.html.haml
+++ b/app/views/story_group_invites/quick.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Kod dla studentów'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_group_invites/show.html.haml b/app/views/story_group_invites/show.html.haml
index 7091a453..5444c2c3 100644
--- a/app/views/story_group_invites/show.html.haml
+++ b/app/views/story_group_invites/show.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Zaproszenie #{@invite.code}"
+- content_for :title, t('.page_title', code: @invite.code)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_group_memberships/_confirm_leave.html.haml b/app/views/story_group_memberships/_confirm_leave.html.haml
index 137d7d70..9f123433 100644
--- a/app/views/story_group_memberships/_confirm_leave.html.haml
+++ b/app/views/story_group_memberships/_confirm_leave.html.haml
@@ -1,30 +1,22 @@
 - story_group = membership.story_group
-- badges = membership.students_badges.count
-- items  = membership.students_items.count
-- balance = membership.current_currency.to_i
 
-%h2#gh-leave-title.gh-h2= "Opuścić grupę #{story_group.name}?"
-%p
-  = succeed ':' do
-    Stracisz dostęp do sklepu, rankingu i swojej historii w tej grupie
-  = "#{balance} #{story_group.currency_name},"
-  = "#{badges} #{gh_plural(badges, 'odznaka', 'odznaki', 'odznak')}"
-  = "i #{items} #{gh_plural(items, 'przedmiot', 'przedmioty', 'przedmiotów')}."
+%h2#gh-leave-title.gh-h2= t('.title', name: story_group.name)
+- badges = t('.badges', count: membership.students_badges.count)
+- items  = t('.items', count: membership.students_items.count)
+%p= t('.lose', balance: membership.current_currency.to_i, currency: story_group.currency_name, badges:, items:)
 
 %p.gh-warning-note{ role: 'alert' }
   %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-  %span
-    Tego nie da się cofnąć. Jeśli wrócisz do tej grupy z nowym kodem od
-    prowadzącego, zaczniesz od zera.
+  %span= t('.warning')
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Zostań w grupie
+      = t('.stay')
   - else
-    = link_to 'Zostań w grupie', edit_story_group_membership_path(story_group),
+    = link_to t('.stay'), edit_story_group_membership_path(story_group),
       class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Opuść grupę', story_group_membership_path(story_group),
+  = button_to t('.leave'), story_group_membership_path(story_group),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/story_group_memberships/_nickname.html.haml b/app/views/story_group_memberships/_nickname.html.haml
index 5b9cbb0e..a5926197 100644
--- a/app/views/story_group_memberships/_nickname.html.haml
+++ b/app/views/story_group_memberships/_nickname.html.haml
@@ -1,7 +1,5 @@
-%h2#gh-nick-title.gh-h2= "Pseudonim w grupie #{membership.story_group.name}"
-%p
-  Widoczny w rankingu tylko w tej grupie. W innych grupach możesz mieć inny.
-  Prowadzący widzi też Twoje imię i nazwisko.
+%h2#gh-nick-title.gh-h2= t('.title', name: membership.story_group.name)
+%p= t('.hint')
 
 = form_with model: membership, url: story_group_membership_path(membership.story_group),
   method: :patch, data: { turbo_frame: (@in_modal ? 'modal' : nil) } do |f|
@@ -10,9 +8,9 @@
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
     - else
-      = link_to 'Anuluj', story_group_ranking_path(membership.story_group),
+      = link_to t('shared.actions.cancel'), story_group_ranking_path(membership.story_group),
         class: 'gh-btn gh-btn--secondary'
 
-    %button.gh-btn{ type: 'submit' } Zapisz pseudonim
+    %button.gh-btn{ type: 'submit' }= t('.save')
diff --git a/app/views/story_group_memberships/_nickname_field.html.haml b/app/views/story_group_memberships/_nickname_field.html.haml
index 24c916e0..4e5dac89 100644
--- a/app/views/story_group_memberships/_nickname_field.html.haml
+++ b/app/views/story_group_memberships/_nickname_field.html.haml
@@ -2,7 +2,7 @@
 - autofocus = local_assigns.fetch(:autofocus, false)
 
 .gh-form-field
-  = f.label :nickname, 'Twój pseudonim'
+  = f.label :nickname, t('.label')
   .gh-nickname-field-row
     .gh-text-input{ class: ('gh-text-input--invalid' if error) }
       = f.text_field :nickname, maxlength: 24, autocomplete: 'off', autofocus: autofocus,
@@ -14,4 +14,4 @@
     %p#gh-nickname-error.gh-field-error{ role: 'alert' }
       %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
       %span= error
-  %span.gh-field-hint Do 24 znaków. Zostaw puste, żeby pokazywać imię i nazwisko.
+  %span.gh-field-hint= t('.hint')
diff --git a/app/views/story_group_memberships/confirm_leave.html.haml b/app/views/story_group_memberships/confirm_leave.html.haml
index 58ddde0d..e2b91adc 100644
--- a/app/views/story_group_memberships/confirm_leave.html.haml
+++ b/app/views/story_group_memberships/confirm_leave.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Opuść grupę #{@story_group.name}"
+- content_for :title, t('.page_title', name: @story_group.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_group_memberships/edit.html.haml b/app/views/story_group_memberships/edit.html.haml
index 70006dfc..e192b8f6 100644
--- a/app/views/story_group_memberships/edit.html.haml
+++ b/app/views/story_group_memberships/edit.html.haml
@@ -1,42 +1,40 @@
-- content_for :title, "Ustawienia w grupie - #{@story_group.name}"
+- content_for :title, t('.page_title', name: @story_group.name)
 
 %section.gh-panel.gh-page-header
   %p.gh-breadcrumbs
     = link_to @story_group.name, story_group_path(@story_group)
     %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
-    %span Ustawienia w grupie
-  %h1.gh-h1 Ustawienia w grupie
-  %p.gh-lead= "Te ustawienia dotyczą tylko grupy #{@story_group.name}."
+    %span= t('.title')
+  %h1.gh-h1= t('.title')
+  %p.gh-lead= t('.lead', name: @story_group.name)
 
 %section.gh-panel.gh-settings-section
-  %h2.gh-h3 Pseudonim
-  %p.gh-field-hint Widoczny w rankingu tylko w tej grupie. W innych grupach możesz mieć inny.
+  %h2.gh-h3= t('.nickname')
+  %p.gh-field-hint= t('.nickname_hint')
 
   = form_with model: @membership, url: story_group_membership_path(@story_group), method: :patch do |f|
-    = render 'nickname_field', f: f, membership: @membership, submit_label: 'Zapisz'
+    = render 'nickname_field', f: f, membership: @membership, submit_label: t('shared.actions.save')
 
 %section.gh-panel.gh-settings-section
-  %h2.gh-h3 Co widzi prowadzący
-  %p.gh-field-hint Pozostali studenci widzą tylko Twój pseudonim, i to tylko w rankingu.
+  %h2.gh-h3= t('.teacher_sees')
+  %p.gh-field-hint= t('.teacher_sees_hint')
 
   %ul.gh-visible-fields-list
     %li
-      %span Imię i nazwisko
+      %span= t('.full_name')
       %b= @membership.full_name
     %li
-      %span E-mail
+      %span= t('.email')
       %b= @membership.email
     %li
-      %span Numer indeksu
-      %b= @membership.university_number.presence || 'Brak'
+      %span= t('.university_number')
+      %b= @membership.university_number.presence || t('.none')
 
 %section.gh-panel.gh-danger-zone
-  %h2.gh-h3 Opuść grupę
-  %p.gh-small
-    Stracisz dostęp do grupy, a Twoja waluta, odznaki i przedmioty w niej
-    przepadną. Żeby wrócić, potrzebujesz nowego kodu od prowadzącego.
+  %h2.gh-h3= t('.leave_title')
+  %p.gh-small= t('.leave_body')
   .gh-button-row
     = link_to confirm_leave_story_group_membership_path(@story_group),
       class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-right-from-bracket{ 'aria-hidden': 'true' }
-      Opuść grupę
+      = t('.leave')
diff --git a/app/views/story_group_memberships/nickname.html.haml b/app/views/story_group_memberships/nickname.html.haml
index 543e6c6e..405ef30e 100644
--- a/app/views/story_group_memberships/nickname.html.haml
+++ b/app/views/story_group_memberships/nickname.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Pseudonim w grupie #{@story_group.name}"
+- content_for :title, t('.page_title', name: @story_group.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_groups/_confirm_destroy.html.haml b/app/views/story_groups/_confirm_destroy.html.haml
index 36dc6553..f3a81162 100644
--- a/app/views/story_groups/_confirm_destroy.html.haml
+++ b/app/views/story_groups/_confirm_destroy.html.haml
@@ -1,12 +1,12 @@
 - students = story_group.students.count
 - teachers = story_group.teachers.count + 1
 
-%h2#gh-del-group-title.gh-h2 Usunąć grupę na zawsze?
+%h2#gh-del-group-title.gh-h2= t('.title')
 %p
-  = "#{students} #{gh_plural(students, 'student', 'studenci', 'studentów')}"
-  = "i #{teachers} #{gh_plural(teachers, 'nauczyciel', 'nauczycieli', 'nauczycieli')}"
-  = "#{gh_plural(students + teachers, 'straci', 'stracą', 'straci')} dostęp."
-  Historia, przedmioty i ranking znikną.
+  = t('.lose_access', count:    students + teachers,
+                      students: t('.students', count: students),
+                      teachers: t('.teachers', count: teachers))
+  = t('.gone')
 
 = form_with url: story_group_path(story_group), method: :delete,
   data: { controller: 'confirm-name',
@@ -15,7 +15,7 @@
 
   .gh-form-field
     = label_tag :confirm do
-      Wpisz nazwę grupy, żeby potwierdzić:
+      = t('.confirm')
       %b= story_group.name
     .gh-text-input{ class: ('gh-text-input--invalid' if @confirm_failed) }
       = text_field_tag :confirm, nil, autocomplete: 'off', autofocus: true,
@@ -25,14 +25,14 @@
     - if @confirm_failed
       %p#gh-del-group-error.gh-field-error{ role: 'alert' }
         %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-        %span Wpisana nazwa nie zgadza się z nazwą grupy. Grupa nie została usunięta.
+        %span= t('.mismatch')
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
     - else
-      = link_to 'Anuluj', edit_story_group_path(story_group), class: 'gh-btn gh-btn--secondary'
+      = link_to t('shared.actions.cancel'), edit_story_group_path(story_group), class: 'gh-btn gh-btn--secondary'
 
     %button.gh-btn{ type: 'submit', disabled: true,
                     data: { confirm_name_target: 'submit' } }
-      Usuń grupę
+      = t('.remove')
diff --git a/app/views/story_groups/_currency_mini.html.haml b/app/views/story_groups/_currency_mini.html.haml
index 6aa40ed4..e2ad6621 100644
--- a/app/views/story_groups/_currency_mini.html.haml
+++ b/app/views/story_groups/_currency_mini.html.haml
@@ -5,7 +5,7 @@
         %span{ data: { group_wizard_target: 'markLetter' } }
     %span
       %b 19
-      %small do wydania
+      %small= t('.to_spend')
 
   %span.gh-currency-preview-purse
     %span.gh-currency-token.gh-octagon-clip{ style: '--gh-s: 50px', 'aria-hidden': 'true' }
diff --git a/app/views/story_groups/_group_card.html.haml b/app/views/story_groups/_group_card.html.haml
index d34a5a22..1281e93c 100644
--- a/app/views/story_groups/_group_card.html.haml
+++ b/app/views/story_groups/_group_card.html.haml
@@ -13,5 +13,5 @@
         %span{ class: "gh-tag gh-role-tag gh-tag--#{group.role}" }= group.role_label
 
         %p.gh-group-index-meta
-          %span= "#{group.students_count} #{gh_plural(group.students_count, 'student', 'studentów', 'studentów')}"
+          %span= t('.students', count: group.students_count)
           %span= group.meta
diff --git a/app/views/story_groups/_preset_review.html.haml b/app/views/story_groups/_preset_review.html.haml
index f722213c..8a73850f 100644
--- a/app/views/story_groups/_preset_review.html.haml
+++ b/app/views/story_groups/_preset_review.html.haml
@@ -1,12 +1,12 @@
 - preset = @preset
-- currency = @currency_name.presence || 'waluty'
+-# Not t('.x'): the render layout: blocks below run inside preset_row and would read its keys.
+- tr = ->(key, **vars) { t("story_groups.preset_review.#{key}", **vars) }
+- currency = @currency_name.presence || tr.call(:currency_fallback)
 
 = turbo_frame_tag 'starter_pack' do
   .gh-form-section.gh-form-section--first
-    %h2.gh-h3= "Zestaw „#{preset.label}” dla #{preset.classes} zajęć"
-    %p.gh-field-hint
-      Usuń, czego nie potrzebujesz, i popraw liczby. Nazwy i opisy zmienisz po
-      utworzeniu grupy.
+    %h2.gh-h3= tr.call(:title, pack: preset.label, classes: preset.classes)
+    %p.gh-field-hint= tr.call(:hint)
 
     = hidden_field_tag 'setup[pack]', preset.pack, id: nil
     = hidden_field_tag 'setup[classes]', preset.classes, id: nil
@@ -14,34 +14,34 @@
     .gh-preset-review-grid
       %section.gh-preset-review-section
         %h3.gh-h3
-          Rangi
+          = tr.call(:ranks)
           %span.gh-showcase-zone-count.gh-octagon-clip= preset.ranks.size
         - preset.ranks.each do |rank|
           = render layout: 'preset_row', locals: { zone: 'ranks', index: rank.index, icon: 'fa-ranking-star',
             name: rank.name,
-            note: (rank.discount.positive? ? "−#{rank.discount}% w sklepie" : 'Ranga startowa') } do
+            note: (rank.discount.positive? ? tr.call(:shop_discount, discount: rank.discount) : tr.call(:starting_rank)) } do
             - if rank.index.zero?
-              %span.gh-preset-row-value od 0
+              %span.gh-preset-row-value= tr.call(:from_zero)
               = hidden_field_tag "setup[ranks][#{rank.index}][value]", rank.threshold, id: nil
             - else
               %span.gh-preset-row-value
-                od
+                = tr.call(:from)
                 .gh-text-input.gh-input--compact
                   = number_field_tag "setup[ranks][#{rank.index}][value]", rank.threshold,
-                    min: 0, step: 1, id: nil, 'aria-label': "#{rank.name}: próg"
+                    min: 0, step: 1, id: nil, 'aria-label': tr.call(:threshold_label, name: rank.name)
 
       %section.gh-preset-review-section
         %h3.gh-h3
-          Odznaki
+          = tr.call(:badges)
           %span.gh-showcase-zone-count.gh-octagon-clip= preset.badges.size
         - preset.badges.each do |badge|
           = render layout: 'preset_row', locals: { zone: 'badges', index: badge.index, icon: 'fa-award',
             name: badge.name, note: badge.didactic_description } do
-            %span.gh-preset-row-value= "−#{badge.discount}% w sklepie"
+            %span.gh-preset-row-value= tr.call(:shop_discount, discount: badge.discount)
 
       %section.gh-preset-review-section
         %h3.gh-h3
-          Przedmioty w sklepie
+          = tr.call(:items)
           %span.gh-showcase-zone-count.gh-octagon-clip= preset.items.size
         - preset.items.each do |item|
           = render layout: 'preset_row', locals: { zone: 'items', index: item.index, icon: 'fa-bag-shopping',
@@ -49,15 +49,15 @@
             %span.gh-preset-row-value
               .gh-text-input.gh-input--compact
                 = number_field_tag "setup[items][#{item.index}][value]", item.price,
-                  min: 1, step: 1, id: nil, 'aria-label': "#{item.name}: cena w #{currency}"
+                  min: 1, step: 1, id: nil, 'aria-label': tr.call(:price_label, name: item.name, currency: currency)
               %span.gh-currency-token.gh-octagon-clip{ style: '--gh-s: 20px', 'aria-hidden': 'true' }
                 %span.gh-octagon-clip{ data: { group_wizard_target: 'markBox' } }
                   %span{ data: { group_wizard_target: 'markLetter' } }
 
       %section.gh-preset-review-section
         %h3.gh-h3
-          Kategorie zajęć
-          %small.gh-page-kicker= "(szablon „#{StarterPack::TEMPLATE_NAME}”)"
+          = tr.call(:categories)
+          %small.gh-page-kicker= tr.call(:template, name: StarterPack.template_name)
           %span.gh-showcase-zone-count.gh-octagon-clip= preset.categories.size
         - preset.categories.each do |category|
           = render layout: 'preset_row', locals: { zone: 'cats', index: category.index, icon: 'fa-table-cells',
@@ -66,7 +66,7 @@
               .gh-text-input.gh-input--compact
                 = number_field_tag "setup[cats][#{category.index}][value]", category.reward,
                   min: 1, step: 1, id: nil,
-                  'aria-label': "#{category.didactic_description}: nagroda w #{currency}"
+                  'aria-label': tr.call(:reward_label, name: category.didactic_description, currency: currency)
               %span.gh-currency-token.gh-octagon-clip{ style: '--gh-s: 20px', 'aria-hidden': 'true' }
                 %span.gh-octagon-clip{ data: { group_wizard_target: 'markBox' } }
                   %span{ data: { group_wizard_target: 'markLetter' } }
diff --git a/app/views/story_groups/_preset_row.html.haml b/app/views/story_groups/_preset_row.html.haml
index b432ee99..f94f5c7c 100644
--- a/app/views/story_groups/_preset_row.html.haml
+++ b/app/views/story_groups/_preset_row.html.haml
@@ -1,6 +1,8 @@
 - row_id = "gh-preset-#{zone}-#{index}"
 
-.gh-preset-row{ data: { controller: 'preset-row' } }
+.gh-preset-row{ data: { controller: 'preset-row', preset_row_name_value: name,
+                          preset_row_remove_value: t('.remove', name: '%{name}'),
+                          preset_row_restore_value: t('.restore', name: '%{name}') } }
   %i.fa-solid{ class: icon, 'aria-hidden': 'true' }
 
   %span.gh-preset-row-name
@@ -15,5 +17,5 @@
   %label.gh-preset-row-remove{ for: row_id }
     = check_box_tag "setup[#{zone}][#{index}][keep]", '1', true, id: row_id,
       class: 'sr-only', data: { preset_row_target: 'keep', action: 'preset-row#toggle' }
-    %span.sr-only{ data: { preset_row_target: 'label' } }= "Usuń: #{name}"
+    %span.sr-only{ data: { preset_row_target: 'label' } }= t('.remove', name: name)
     %i.fa-solid.fa-xmark{ 'aria-hidden': 'true', data: { preset_row_target: 'icon' } }
diff --git a/app/views/story_groups/_settings.html.haml b/app/views/story_groups/_settings.html.haml
index 87f200e5..691e035c 100644
--- a/app/views/story_groups/_settings.html.haml
+++ b/app/views/story_groups/_settings.html.haml
@@ -1,21 +1,19 @@
 - error = ->(attribute) { story_group.errors[attribute].first }
 
 %section.gh-panel.gh-page-header
-  %h1.gh-h1 Ustawienia grupy
-  %p.gh-lead
-    Zmienią je wszyscy prowadzący tę grupę. Tylko właściciel może usunąć grupę.
-    Ranking ustawiasz w zakładce Ranking.
+  %h1.gh-h1= t('.title')
+  %p.gh-lead= t('.lead')
 
 = form_with model: story_group do |f|
   %section.gh-panel.gh-settings-section
     .gh-form-section.gh-form-section--first
-      %h2.gh-h3 Grupa i opowieść
+      %h2.gh-h3= t('.group_section')
 
       .gh-form-field
-        = f.label :name, 'Nazwa grupy'
+        = f.label :name, t('.name')
         .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:name)) }
           = f.text_field :name, maxlength: 40, autocomplete: 'off',
-            placeholder: 'np. Kosmiczne króliki',
+            placeholder: t('.name_placeholder'),
             'aria-invalid': (error.call(:name) ? 'true' : nil),
             'aria-describedby': (error.call(:name) ? 'gh-group-name-error' : nil)
         - if error.call(:name)
@@ -24,7 +22,7 @@
             %span= error.call(:name)
 
       .gh-form-field
-        = f.label :description, 'Opowieść'
+        = f.label :description, t('.story')
         .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:description)) }
           = f.text_area :description, rows: 3, maxlength: 1024,
             'aria-invalid': (error.call(:description) ? 'true' : nil),
@@ -33,53 +31,49 @@
           %p#gh-group-story-error.gh-field-error{ role: 'alert' }
             %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
             %span= error.call(:description)
-        %span.gh-field-hint Widzą ją wszyscy w grupie, na stronie głównej grupy.
+        %span.gh-field-hint= t('.story_hint')
 
       = render 'shared/image_field', form: f, record: story_group,
         presets: GroupArt::KEYS, registry: GroupArt,
         kind: 'group', tile: :art,
-        copy: { label: 'Grafika grupy',
-                hint: 'JPG lub PNG, najlepiej co najmniej 1200 px szerokości.' }
+        copy: { label: t('.art_label'),
+                hint: t('.art_hint') }
 
     .gh-form-section
-      %h2.gh-h3 Waluta
-      %p.gh-field-hint Nowa nazwa pojawi się wszędzie, także w historii studentów.
+      %h2.gh-h3= t('.currency_section')
+      %p.gh-field-hint= t('.currency_hint')
 
       .gh-form-field
-        = f.label :currency_name, 'Nazwa waluty'
+        = f.label :currency_name, t('.currency_name')
         .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:currency_name)) }
           = f.text_field :currency_name, maxlength: 40, autocomplete: 'off',
-            placeholder: 'np. Marchewek',
+            placeholder: t('.currency_placeholder'),
             'aria-invalid': (error.call(:currency_name) ? 'true' : nil),
             'aria-describedby': (error.call(:currency_name) ? 'gh-group-currency-error' : nil)
         - if error.call(:currency_name)
           %p#gh-group-currency-error.gh-field-error{ role: 'alert' }
             %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
             %span= error.call(:currency_name)
-        %span.gh-field-hint Podaj ją w formie, która pasuje do liczby — np. „Marchewek”.
+        %span.gh-field-hint= t('.currency_name_hint')
 
       = render 'shared/image_field', form: f, record: story_group,
         attribute: :currency_icon, glyph_attribute: :currency_icon_glyph,
         presets: CurrencyIcons::KEYS, registry: CurrencyIcons,
         kind: 'currency', tile: :currency, aspect: 1,
-        copy: { label: 'Ikona waluty', presets: 'Gotowe ikony',
-                own: 'Twoja ikona', upload: 'Albo wgraj własną ikonę',
-                hint: 'Najlepiej PNG z przezroczystym tłem, co najmniej 128 px.',
-                crop: 'Przytnij ikonę',
-                cropped: 'Przesuń i przeskaluj zaznaczenie. Zapisujemy kwadratowy kadr, bo ikona siada na okrągłym liczmanie.' }
+        copy: t('story_groups.currency_icon')
 
     .gh-form-section
-      %h2.gh-h3 Życia
+      %h2.gh-h3= t('.lives_section')
       .gh-form-field{ data: { controller: 'lives-stepper', lives_stepper_max_value: 10 } }
-        %p#gh-default-lives-label.gh-form-label Życia na start
+        %p#gh-default-lives-label.gh-form-label= t('.lives')
         .gh-number-stepper{ role: 'group', 'aria-labelledby': 'gh-default-lives-label' }
-          %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Mniej',
+          %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('shared.actions.fewer'),
                               disabled: story_group.default_lives.to_i.zero?,
                               data: { lives_stepper_target: 'down',
                                       action: 'lives-stepper#down' } }
             %i.fa-solid.fa-minus{ 'aria-hidden': 'true' }
           %output{ 'aria-live': 'polite', data: { lives_stepper_target: 'output' } }= story_group.default_lives
-          %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Więcej',
+          %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('shared.actions.more'),
                               disabled: story_group.default_lives.to_i >= 10,
                               data: { lives_stepper_target: 'up',
                                       action: 'lives-stepper#up' } }
@@ -92,23 +86,19 @@
             %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
             %span= error.call(:default_lives)
 
-        %span.gh-field-hint
-          Dotyczy tylko studentów, którzy dołączą od teraz. Obecnym zmieniasz
-          życia na liście studentów.
+        %span.gh-field-hint= t('.lives_hint')
 
   .gh-panel.gh-form-actions-bar
-    = link_to 'Wróć do grupy', story_group_path(story_group), class: 'gh-link-button'
+    = link_to t('.back'), story_group_path(story_group), class: 'gh-link-button'
     %span.gh-form-actions-spacer
-    %button.gh-btn{ type: 'submit' } Zapisz zmiany
+    %button.gh-btn{ type: 'submit' }= t('shared.actions.save_changes')
 
 - if policy(story_group).destroy?
   %section.gh-panel.gh-danger-zone
-    %h2.gh-h3 Usuń grupę
-    %p.gh-small
-      Usunięcie zabiera wszystkim dostęp do grupy, jej sklepu, rankingu
-      i historii. Tego nie da się cofnąć.
+    %h2.gh-h3= t('.delete_title')
+    %p.gh-small= t('.delete_body')
     .gh-button-row
       = link_to confirm_destroy_story_group_path(story_group),
         class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-        Usuń grupę
+        = t('.delete')
diff --git a/app/views/story_groups/_student_show.html.haml b/app/views/story_groups/_student_show.html.haml
index 32b5cec7..4cf56864 100644
--- a/app/views/story_groups/_student_show.html.haml
+++ b/app/views/story_groups/_student_show.html.haml
@@ -11,12 +11,12 @@
           %h1.gh-h1= story_group.name
           - if story_group.description.present?
             %p.gh-group-description-text= story_group.description
-          %p.gh-small.gh-group-description-card-action Prowadzi #{story_group.owner.full_name}
+          %p.gh-small.gh-group-description-card-action= t('.led_by', name: story_group.owner.full_name)
 
-  %section.gh-card.gh-card--rank.gh-currency-balance-card{ 'aria-label': "Twoje #{story_group.currency_name}" }
+  %section.gh-card.gh-card--rank.gh-currency-balance-card{ 'aria-label': t('.balance_label', currency: story_group.currency_name) }
     .gh-card-frame
       .gh-card-inset
-        %p.gh-page-kicker Do wydania
+        %p.gh-page-kicker= t('.to_spend')
         .gh-big-number-row
           = render 'layouts/currency_token', story_group: story_group, size: 44
           %span.gh-tabular-nums= overview.balance
@@ -24,10 +24,10 @@
 
         %dl.gh-currency-balance-stats
           %div
-            %dt Zebrane łącznie
+            %dt= t('.collected')
             %dd= overview.total
           %div
-            %dt Życia
+            %dt= t('.lives')
             %dd
               %span.gh-lives-badge{ class: ('gh-lives-badge--zero' if overview.lives.zero?) }
                 %i.fa-solid.fa-heart{ 'aria-hidden': 'true' }
@@ -35,14 +35,14 @@
 
         = link_to story_group_shop_index_path(story_group), class: 'gh-btn' do
           %i.fa-solid.fa-bag-shopping{ 'aria-hidden': 'true' }
-          Otwórz sklep
+          = t('.open_shop')
 
   %section.gh-card.gh-card--rank.gh-rank-card
     .gh-card-frame
       .gh-card-inset
         .gh-rank-card-top
-          %p.gh-page-kicker Twoja ranga
-          %h2.gh-rank-card-name= overview.rank&.name || 'Brak rangi'
+          %p.gh-page-kicker= t('.your_rank')
+          %h2.gh-rank-card-name= overview.rank&.name || t('.no_rank')
 
         - if overview.rank
           .gh-card-art
@@ -52,21 +52,19 @@
           - progress, span = overview.rank_progress
           .gh-rank-progress
             .gh-rank-progress-text
-              %span #{overview.total} z #{overview.next_rank.required_currency_value}
+              %span= t('.progress', total: overview.total, needed: overview.next_rank.required_currency_value)
               %span= overview.next_rank.name
             .gh-progress-bar.gh-octagon-clip{ role:              'progressbar',
                      'aria-valuemin': 0,
                      'aria-valuemax': span,
                      'aria-valuenow': progress,
-                     'aria-label':    'Postęp do następnej rangi', }
+                     'aria-label':    t('.progress_label'), }
               %i.gh-octagon-clip{ style: "--gh-p: #{gh_percent(progress, span)}%" }
             %p.gh-small= overview_next_rank_line(overview.missing_to_next_rank, overview.next_rank)
         - elsif overview.rank
-          %p.gh-small #{overview.total} zebranych. To najwyższa ranga w tej grupie.
+          %p.gh-small= t('.top_rank', total: overview.total)
         - else
-          %p.gh-small
-            Prowadzący nie dodał jeszcze rang. Waluta, którą zbierasz, liczy się
-            mimo to — rangi przyznają się same, gdy się pojawią.
+          %p.gh-small= t('.no_ranks')
 
         - if overview.ranking_place
           %p.gh-small.gh-rank-card-footer
@@ -76,8 +74,8 @@
   - if shelf.any?
     %section.gh-showcase-zone.gh-showcase-zone--badges
       %h2.gh-showcase-zone-label
-        %span Odznaki
-        %span.gh-showcase-zone-count.gh-octagon-clip #{shelf.earned_count} z #{shelf.size}
+        %span= t('.badges')
+        %span.gh-showcase-zone-count.gh-octagon-clip= t('.badges_count', earned: shelf.earned_count, total: shelf.size)
       .gh-card-grid.gh-card-grid--compact
         - shelf.slots.each do |slot|
           = render 'badges/flip_card', badge:       slot.badge,
@@ -87,7 +85,7 @@
 
   %section.gh-showcase-zone.gh-showcase-zone--hand
     %h2.gh-showcase-zone-label
-      %span Twoje przedmioty
+      %span= t('.items')
       %span.gh-showcase-zone-count.gh-octagon-clip= overview.items_count
     .gh-item-hand
       - count = overview.items.size
@@ -97,10 +95,10 @@
 
       .gh-panel.gh-empty-slot-panel
         %p= overview_hand_line(overview.affordable)
-        = link_to 'Przejdź do sklepu', story_group_shop_index_path(story_group), class: 'gh-btn gh-btn--secondary'
+        = link_to t('.go_to_shop'), story_group_shop_index_path(story_group), class: 'gh-btn gh-btn--secondary'
 
   %section.gh-panel.gh-overview-ledger-panel{ 'aria-labelledby': 'gh-ledger-title' }
-    %h2#gh-ledger-title.gh-h2 Ostatnie zmiany
+    %h2#gh-ledger-title.gh-h2= t('.recent')
     - if overview.entries.any?
       %ul.gh-ledger-list
         - overview.entries.each do |entry|
@@ -108,13 +106,11 @@
             %span.gh-activity-feed-row-marker{ class: "gh-activity-feed-row-marker--#{entry.tone}", 'aria-hidden': 'true' }
             %span.gh-activity-feed-row-text
               = entry.title
-              %small #{entry.label}, #{gh_when(entry.occurred_at)}
+              %small= t('.entry_meta', label: entry.label, when: gh_when(entry.occurred_at))
             %span.gh-activity-feed-row-amount{ class: "gh-activity-feed-row-amount--#{entry.tone}" }= entry.signed_amount
 
-      = link_to 'Pokaż całą historię',
+      = link_to t('.full_history'),
                 story_group_student_currency_transactions_path(story_group, overview.student),
                 class: 'gh-link-button'
     - else
-      %p.gh-explainer-note
-        Pierwsze wpisy pojawią się po zajęciach. Prowadzący przyznaje walutę za
-        obecność, punktualność i aktywność.
+      %p.gh-explainer-note= t('.no_entries')
diff --git a/app/views/story_groups/_teacher_show.html.haml b/app/views/story_groups/_teacher_show.html.haml
index 96e34068..734023ac 100644
--- a/app/views/story_groups/_teacher_show.html.haml
+++ b/app/views/story_groups/_teacher_show.html.haml
@@ -12,16 +12,16 @@
         .gh-button-row
           = link_to story_group_invites_path(story_group), class: 'gh-btn' do
             %i.fa-solid.fa-qrcode{ 'aria-hidden': 'true' }
-            Pokaż kod dla studentów
+            = t('.show_code')
           = link_to story_group_activity_groups_path(story_group), class: 'gh-btn gh-btn--secondary' do
             %i.fa-solid.fa-table{ 'aria-hidden': 'true' }
-            Utwórz arkusz
+            = t('.create_sheet')
           - if policy(story_group).update?
             = link_to edit_story_group_path(story_group), class: 'gh-btn gh-btn--secondary' do
               %i.fa-solid.fa-gear{ 'aria-hidden': 'true' }
-              Ustawienia grupy
+              = t('.settings')
 
-%section.gh-panel.gh-stat-row{ 'aria-label': 'Podsumowanie grupy' }
+%section.gh-panel.gh-stat-row{ 'aria-label': t('.summary') }
   %dl
     - overview.stat_tiles.each do |tile|
       .gh-stat-tile
@@ -33,7 +33,7 @@
 
 .gh-overview-grid
   %section.gh-panel.gh-overview-side-panel{ 'aria-labelledby': 'gh-purchases-title' }
-    %h2#gh-purchases-title.gh-h2 Ostatnie zakupy
+    %h2#gh-purchases-title.gh-h2= t('.purchases')
 
     - if overview.purchases.any?
       %ul.gh-purchase-list
@@ -41,23 +41,21 @@
           %li.gh-purchase-row.gh-purchase-row--group-variant
             = render 'layouts/item_thumb', item: purchase.item
             %span.gh-purchase-row-main
-              %b= purchase.item&.name || 'Przedmiot usunięty z oferty'
+              %b= purchase.item&.name || t('.removed_item')
               %span= purchase.student_name
             %span.gh-price-badge
               %b= purchase.price
               = render 'layouts/currency_token', story_group: story_group, size: 16
             %span.gh-purchase-row-time= gh_when(purchase.time)
 
-      = link_to 'Wszystkie zakupy w grupie', home_path(group: story_group.id), class: 'gh-link-button'
+      = link_to t('.all_purchases'), home_path(group: story_group.id), class: 'gh-link-button'
     - else
-      %p.gh-explainer-note
-        Nikt jeszcze niczego nie kupił. Zakupy pojawią się tutaj same, gdy
-        studenci zaczną wydawać walutę w sklepie.
+      %p.gh-explainer-note= t('.no_purchases')
 
   .gh-overview-column
     - if overview.attention.any?
       %section.gh-panel.gh-overview-side-panel{ 'aria-labelledby': 'gh-attention-title' }
-        %h2#gh-attention-title.gh-h2 Wymaga uwagi
+        %h2#gh-attention-title.gh-h2= t('.attention')
         %ul.gh-attention-list
           - overview.attention.each do |row|
             %li
@@ -71,12 +69,12 @@
 
     - if overview.recent_sheets.any?
       %section.gh-panel.gh-overview-side-panel{ 'aria-labelledby': 'gh-sheets-title' }
-        %h2#gh-sheets-title.gh-h2 Ostatnie arkusze
+        %h2#gh-sheets-title.gh-h2= t('.recent_sheets')
         - overview.recent_sheets.each do |sheet|
           .gh-sheet-summary-row
             %div
               %b= sheet.activity_group.name
-              = link_to 'Otwórz', story_group_activity_groups_path(story_group), class: 'gh-link-button'
+              = link_to t('.open'), story_group_activity_groups_path(story_group), class: 'gh-link-button'
             - if sheet.podium.any?
               %ol.gh-leaderboard-top3
                 - sheet.podium.each_with_index do |place, index|
@@ -86,11 +84,9 @@
                     %span.gh-leaderboard-score +#{place.points}
               %p.gh-small= ranking_visibility_note(story_group)
             - else
-              %p.gh-small Nikt nie ma jeszcze nagród z tego arkusza.
+              %p.gh-small= t('.no_rewards')
     - else
       %section.gh-panel.gh-overview-side-panel
-        %h2.gh-h2 Nie masz jeszcze arkuszy ocen
-        %p.gh-explainer-note
-          Arkusz to jedne zajęcia: kolumny z nagrodami i lista studentów.
-          Utwórz pierwszy, żeby zacząć przyznawać walutę.
-        = link_to 'Utwórz arkusz', story_group_activity_groups_path(story_group), class: 'gh-btn gh-btn--secondary'
+        %h2.gh-h2= t('.no_sheets_title')
+        %p.gh-explainer-note= t('.no_sheets_body')
+        = link_to t('.create_sheet'), story_group_activity_groups_path(story_group), class: 'gh-btn gh-btn--secondary'
diff --git a/app/views/story_groups/_wizard.html.haml b/app/views/story_groups/_wizard.html.haml
index 40650f97..e63be5d8 100644
--- a/app/views/story_groups/_wizard.html.haml
+++ b/app/views/story_groups/_wizard.html.haml
@@ -1,22 +1,22 @@
 - error  = ->(attribute) { story_group.errors[attribute].first }
 - packs  = StarterPack
 
-- steps = ['Grupa i opowieść', 'Waluta i zasady', 'Jak zaczynasz', 'Podsumowanie']
+- steps = t('.steps')
 
 .gh-wizard{ data: { controller: 'group-wizard',
                     action: 'gh:image-crop->group-wizard#art',
-                    group_wizard_preset_url_value: preset_preview_story_groups_path } }
+                    group_wizard_preset_url_value: preset_preview_story_groups_path,
+                    group_wizard_i18n_value: t('.js').to_json } }
 
   %section.gh-panel.gh-page-header.gh-page-header--stacked
     %p.gh-breadcrumbs
-      = link_to 'Grupy', story_groups_path
+      = link_to t('.breadcrumb'), story_groups_path
       %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
-      %span Nowa grupa
-    %h1.gh-h1 Nowa grupa
-    %p.gh-lead
-      Zajmie to kilka minut. Wszystko zmienisz później w ustawieniach grupy.
+      %span= t('.title')
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= t('.lead')
 
-    %nav.gh-wizard-steps{ 'aria-label': 'Kroki' }
+    %nav.gh-wizard-steps{ 'aria-label': t('.steps_label') }
       - steps.each_with_index do |label, index|
         %button.gh-wizard-step-tab{ type: 'button', disabled: index.positive?,
                         'aria-current': (index.zero? ? 'step' : nil),
@@ -42,63 +42,60 @@
       %section.gh-panel.gh-form-column
 
         %section{ data: { group_wizard_target: 'panel' } }
-          %h2.sr-only Grupa i opowieść
+          %h2.sr-only= steps[0]
 
           .gh-form-section.gh-form-section--first
-            %h2.gh-h3 Nazwa i opowieść
-            %p.gh-field-hint Studenci zobaczą je na liście grup i na stronie grupy.
+            %h2.gh-h3= t('.name_section')
+            %p.gh-field-hint= t('.name_hint')
 
             .gh-form-field
-              = f.label :name, 'Nazwa grupy'
+              = f.label :name, t('.name')
               .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:name)) }
                 = f.text_field :name, maxlength: 40, autocomplete: 'off',
-                  placeholder: 'np. Zakon Algorytmów',
+                  placeholder: t('.name_placeholder'),
                   'aria-invalid': (error.call(:name) ? 'true' : nil),
                   'aria-describedby': (error.call(:name) ? 'gh-wiz-name-error' : nil),
                   data: { group_wizard_target: 'name', action: 'group-wizard#refresh' }
               %p#gh-wiz-name-error.gh-field-error{ role: 'alert', hidden: error.call(:name).blank?,
                                            data: { group_wizard_target: 'nameError' } }
                 %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-                %span= error.call(:name) || 'Podaj nazwę grupy.'
+                %span= error.call(:name) || t('.name_missing')
 
             .gh-form-field
               = f.label :description do
-                Opowieść
-                %small (opcjonalnie)
+                = t('.story')
+                %small= t('shared.actions.optional')
               .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:description)) }
                 = f.text_area :description, rows: 4, maxlength: 1024,
-                  placeholder: 'Dawno, dawno temu…'
+                  placeholder: t('.story_placeholder')
               - if error.call(:description)
                 %p.gh-field-error{ role: 'alert' }
                   %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
                   %span= error.call(:description)
-              %span.gh-field-hint Krótki wstęp fabularny. Zmienisz go w każdej chwili.
+              %span.gh-field-hint= t('.story_hint')
 
           .gh-form-section
-            %h2.gh-h3 Grafika grupy
-            %p.gh-field-hint
-              Pojawia się na karcie grupy, w panelu bocznym i jako tło grupy.
+            %h2.gh-h3= t('.art_section')
+            %p.gh-field-hint= t('.art_hint')
 
             = render 'shared/image_field', form: f, record: story_group,
               presets: GroupArt::KEYS, registry: GroupArt,
               kind: 'group', tile: :art, refresh_action: 'group-wizard#art',
-              copy: { label: 'Grafika grupy',
-                      hint: 'JPG lub PNG, najlepiej co najmniej 1200 px szerokości.' }
+              copy: { label: t('story_groups.settings.art_label'),
+                      hint: t('story_groups.settings.art_hint') }
 
         %section{ data: { group_wizard_target: 'panel' }, hidden: true }
-          %h2.sr-only Waluta i zasady
+          %h2.sr-only= steps[1]
 
           .gh-form-section.gh-form-section--first
-            %h2.gh-h3 Nazwa waluty
-            %p.gh-field-hint
-              Czytamy ją po każdej liczbie, więc podaj formę, która pasuje do
-              liczby mnogiej — np. „Marchewek”.
+            %h2.gh-h3= t('.currency_section')
+            %p.gh-field-hint= t('.currency_hint')
 
             .gh-form-field
-              = f.label :currency_name, 'Nazwa waluty'
+              = f.label :currency_name, t('.currency_name')
               .gh-text-input{ class: ('gh-text-input--invalid' if error.call(:currency_name)) }
                 = f.text_field :currency_name, maxlength: 40, autocomplete: 'off',
-                  placeholder: 'np. Złotych Monet',
+                  placeholder: t('.currency_placeholder'),
                   'aria-invalid': (error.call(:currency_name) ? 'true' : nil),
                   'aria-describedby': (error.call(:currency_name) ? 'gh-wiz-currency-error' : nil),
                   data: { group_wizard_target: 'currency', action: 'group-wizard#refresh' }
@@ -106,32 +103,28 @@
                                                hidden: error.call(:currency_name).blank?,
                                                data: { group_wizard_target: 'currencyError' } }
                 %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-                %span= error.call(:currency_name) || 'Podaj nazwę waluty.'
+                %span= error.call(:currency_name) || t('.currency_missing')
 
             = render 'shared/image_field', form: f, record: story_group,
               attribute: :currency_icon, glyph_attribute: :currency_icon_glyph,
               presets: CurrencyIcons::KEYS, registry: CurrencyIcons,
               kind: 'currency', tile: :currency, aspect: 1,
               refresh_action: 'group-wizard#refresh',
-              copy: { label: 'Ikona waluty', presets: 'Gotowe ikony',
-                      own: 'Twoja ikona', upload: 'Albo wgraj własną ikonę',
-                      hint: 'Najlepiej PNG z przezroczystym tłem, co najmniej 128 px.',
-                      crop: 'Przytnij ikonę',
-                      cropped: 'Przesuń i przeskaluj zaznaczenie. Zapisujemy kwadratowy kadr, bo ikona siada na okrągłym liczmanie.' }
+              copy: t('story_groups.currency_icon')
 
           .gh-form-section
-            %h2.gh-h3 Życia
+            %h2.gh-h3= t('.lives_section')
             .gh-form-field{ data: { controller: 'lives-stepper', lives_stepper_max_value: 10 } }
-              %p#gh-wiz-lives-label.gh-form-label Życia na start
+              %p#gh-wiz-lives-label.gh-form-label= t('.lives')
               .gh-number-stepper{ role: 'group', 'aria-labelledby': 'gh-wiz-lives-label' }
-                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Mniej żyć',
+                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('.fewer_lives'),
                                     disabled: story_group.default_lives.to_i.zero?,
                                     data: { lives_stepper_target: 'down',
                                             action: 'lives-stepper#down' } }
                   %i.fa-solid.fa-minus{ 'aria-hidden': 'true' }
                 %output{ 'aria-live': 'polite',
                          data: { lives_stepper_target: 'output' } }= story_group.default_lives
-                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Więcej żyć',
+                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('.more_lives'),
                                     disabled: story_group.default_lives.to_i >= 10,
                                     data: { lives_stepper_target: 'up',
                                             action: 'lives-stepper#up' } }
@@ -144,12 +137,10 @@
                   %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
                   %span= error.call(:default_lives)
 
-              %span.gh-field-hint
-                Przy 0 życiach student kupi tylko przedmioty oznaczone jako
-                dostępne przy 0 życiach.
+              %span.gh-field-hint= t('.lives_hint')
 
           .gh-form-section
-            %h2.gh-h3 Ranking
+            %h2.gh-h3= t('.ranking_section')
 
             .gh-toggle-switch-row
               = f.check_box :ranking_enabled, class: 'gh-toggle-switch gh-octagon-clip', role: 'switch',
@@ -157,60 +148,51 @@
                 data: { group_wizard_target: 'ranking',
                         action: 'change->group-wizard#refresh' }
               %span
-                %b#gh-wiz-ranking-label Pokazuj ranking studentom
-                %span.gh-field-hint
-                  Domyślnie wyłączony. Możesz go włączyć w każdej chwili
-                  w zakładce Ranking.
+                %b#gh-wiz-ranking-label= t('.ranking')
+                %span.gh-field-hint= t('.ranking_hint')
 
             .gh-form-field{ hidden: !story_group.ranking_enabled?,
                      data: { group_wizard_target: 'rankingMode' } }
-              = f.label :ranking_mode, 'Co widzą studenci'
+              = f.label :ranking_mode, t('.ranking_mode')
               %span.gh-select-input
                 = f.select :ranking_mode,
-                  StoryGroup.ranking_modes.keys.map { |mode| [StoryGroup::RANKING_MODE_LABELS[mode], mode] },
+                  StoryGroup.ranking_modes.keys.map { |mode| [StoryGroup.ranking_mode_label(mode), mode] },
                   {}, data: { action: 'group-wizard#refresh' }
                 %i.fa-solid.fa-chevron-down{ 'aria-hidden': 'true' }
-              %span.gh-field-hint
-                „Podium i własne miejsce” pokazuje tylko najlepszą trójkę
-                i miejsce studenta. „Pełny ranking” pokazuje całą listę.
+              %span.gh-field-hint= t('.ranking_mode_hint')
 
         %section{ data: { group_wizard_target: 'panel' }, hidden: true }
-          %h2.sr-only Jak zaczynasz
+          %h2.sr-only= steps[2]
 
           .gh-form-section.gh-form-section--first
-            %h2.gh-h3 Jak chcesz zacząć?
-            %p.gh-field-hint Obie drogi dają pełną grupę. Wszystko zmienisz później.
+            %h2.gh-h3= t('.start_section')
+            %p.gh-field-hint= t('.start_hint')
 
-            .gh-choice-grid{ role: 'radiogroup', 'aria-label': 'Sposób startu' }
+            .gh-choice-grid{ role: 'radiogroup', 'aria-label': t('.start_label') }
               %label.gh-choice-card
                 = radio_button_tag 'setup[path]', 'quick', false, class: 'sr-only',
                   id: 'gh-wiz-path-quick',
                   data: { group_wizard_target: 'path', action: 'group-wizard#refresh' }
-                %span.gh-tag.gh-tag--discount Polecane na pierwszą grupę
-                %b Szybki start
-                %span
-                  Gotowe rangi, odznaki, przedmioty i kategorie zajęć.
-                  Przejrzysz je i poprawisz przed utworzeniem grupy.
+                %span.gh-tag.gh-tag--discount= t('.recommended')
+                %b= t('.quick')
+                %span= t('.quick_body')
               %label.gh-choice-card
                 = radio_button_tag 'setup[path]', 'manual', false, class: 'sr-only',
                   id: 'gh-wiz-path-manual',
                   data: { group_wizard_target: 'path', action: 'group-wizard#refresh' }
-                %b Od zera
-                %span
-                  Pusta grupa. Rangi, odznaki i przedmioty dodasz później,
-                  krok po kroku.
+                %b= t('.manual')
+                %span= t('.manual_body')
 
             %p.gh-field-error{ role: 'alert', hidden: true,
                        data: { group_wizard_target: 'pathError' } }
               %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
-              %span Wybierz, jak chcesz zacząć.
+              %span= t('.path_missing')
 
           .gh-form-section{ hidden: true, data: { group_wizard_target: 'quickOnly' } }
-            %h2.gh-h3 Klimat zestawu
-            %p.gh-field-hint
-              Zmienia tylko nazwy rang i odznak. Zasady są wszędzie takie same.
+            %h2.gh-h3= t('.pack_section')
+            %p.gh-field-hint= t('.pack_hint')
 
-            .gh-choice-grid{ role: 'radiogroup', 'aria-label': 'Klimat' }
+            .gh-choice-grid{ role: 'radiogroup', 'aria-label': t('.pack_label') }
               - packs::KEYS.each_with_index do |key, index|
                 %label.gh-choice-card
                   = radio_button_tag 'setup[pack]', key, index.zero?, class: 'sr-only',
@@ -218,23 +200,21 @@
                     data: { group_wizard_target: 'pack', action: 'group-wizard#refresh' }
                   %b= packs.label_for(key)
                   %span= packs.description_for(key)
-                  %em= "#{packs::RANK_NAMES.fetch(key).first(3).join(' → ')} → …"
+                  %em= "#{packs.rank_names(key).first(3).join(' → ')} → …"
 
           .gh-form-section{ hidden: true, data: { group_wizard_target: 'quickOnly' } }
-            %h2.gh-h3 Ile zajęć planujesz?
-            %p.gh-field-hint
-              Dopasujemy progi rang i ceny tak, żeby najwyższa ranga była
-              osiągalna w semestrze.
+            %h2.gh-h3= t('.classes_section')
+            %p.gh-field-hint= t('.classes_hint')
 
             .gh-form-field
-              .gh-number-stepper{ role: 'group', 'aria-label': 'Liczba zajęć' }
-                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Mniej zajęć',
+              .gh-number-stepper{ role: 'group', 'aria-label': t('.classes_label') }
+                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('.fewer_classes'),
                                     data: { group_wizard_target: 'classesDown',
                                             action: 'group-wizard#classesDown' } }
                   %i.fa-solid.fa-minus{ 'aria-hidden': 'true' }
                 %output{ 'aria-live': 'polite',
                          data: { group_wizard_target: 'classesOutput' } }= packs::DEFAULT_CLASSES
-                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Więcej zajęć',
+                %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('.more_classes'),
                                     data: { group_wizard_target: 'classesUp',
                                             action: 'group-wizard#classesUp' } }
                   %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
@@ -243,22 +223,20 @@
                 data: { group_wizard_target: 'classes' }
 
         %section{ data: { group_wizard_target: 'panel' }, hidden: true }
-          %h2.sr-only Podsumowanie
+          %h2.sr-only= steps[3]
 
           .gh-form-section.gh-form-section--first{ hidden: true, data: { group_wizard_target: 'manualSummary' } }
-            %h2.gh-h3 Podsumowanie
-            %p.gh-field-hint
-              Grupa powstanie pusta. Po utworzeniu zobaczysz listę kroków do
-              uzupełnienia.
+            %h2.gh-h3= t('.summary')
+            %p.gh-field-hint= t('.summary_hint')
 
             %dl.gh-summary-list
-              %dt Nazwa
+              %dt= t('shared.actions.name')
               %dd{ data: { group_wizard_target: 'sumName' } }
-              %dt Waluta
+              %dt= t('.summary_currency')
               %dd{ data: { group_wizard_target: 'sumCurrency' } }
-              %dt Życia na start
+              %dt= t('.summary_lives')
               %dd{ data: { group_wizard_target: 'sumLives' } }
-              %dt Ranking
+              %dt= t('.summary_ranking')
               %dd{ data: { group_wizard_target: 'sumRanking' } }
 
           = turbo_frame_tag 'starter_pack',
@@ -266,10 +244,10 @@
                     action: 'turbo:frame-load->group-wizard#refresh' },
             hidden: true
 
-      %aside.gh-preview-column{ 'aria-label': 'Podgląd', data: { group_wizard_target: 'preview' } }
+      %aside.gh-preview-column{ 'aria-label': t('shared.actions.preview'), data: { group_wizard_target: 'preview' } }
 
         %section.gh-panel.gh-preview-panel{ data: { group_wizard_target: 'previewGroup' } }
-          %h3 Karta na liście grup
+          %h3= t('.card_preview')
           %article.gh-card.gh-card--neutral.gh-group-index-card
             .gh-card-frame
               .gh-card-inset
@@ -277,34 +255,33 @@
                   %span{ data: { group_wizard_target: 'artMono' } }
                 .gh-card-header
                   %h2.gh-card-name.gh-placeholder-text{ data: { group_wizard_target: 'nameEcho' } }
-                    Nazwa grupy
+                    = t('.js.name_placeholder')
                 %p.gh-group-index-meta
-                  %span Prowadzisz tę grupę
+                  %span= t('.you_lead')
 
-          %span.gh-field-hint
-            Tło za formularzem pokazuje, jak grafika wygląda jako tło grupy.
+          %span.gh-field-hint= t('.background_hint')
 
         %section.gh-panel.gh-preview-panel{ hidden: true, data: { group_wizard_target: 'previewCurrency' } }
-          %h3 Tak zobaczą walutę studenci
+          %h3= t('.currency_preview')
           .gh-currency-preview-pair
             - %w[light dark].each do |theme|
               = render 'currency_mini', theme: theme
 
     .gh-panel.gh-form-actions-bar
-      = link_to 'Anuluj', story_groups_path, class: 'gh-btn gh-btn--secondary',
+      = link_to t('shared.actions.cancel'), story_groups_path, class: 'gh-btn gh-btn--secondary',
         data: { group_wizard_target: 'cancel' }
-      %button.gh-btn.gh-btn--secondary{ type: 'button', hidden: true, 'aria-label': 'Wstecz',
+      %button.gh-btn.gh-btn--secondary{ type: 'button', hidden: true, 'aria-label': t('.back'),
                                   data: { group_wizard_target: 'back',
                                           action: 'group-wizard#back' } }
         %i.fa-solid.fa-chevron-left{ 'aria-hidden': 'true' }
-        %span.gh-form-actions-bar-label Wstecz
+        %span.gh-form-actions-bar-label= t('.back')
       %span.gh-form-actions-spacer
-      %span.gh-page-kicker{ data: { group_wizard_target: 'counter' } } Krok 1 z 4
+      %span.gh-page-kicker{ data: { group_wizard_target: 'counter' } }= t('.step_counter', step: 1, total: steps.size)
       %button.gh-btn{ type: 'button', data: { group_wizard_target: 'next',
                                               action: 'group-wizard#next' } }
-        %span.gh-form-actions-bar-label{ data: { group_wizard_target: 'nextLabel' } } Dalej
-        %span.gh-form-actions-bar-label--compact{ data: { group_wizard_target: 'nextLabelShort' } } Dalej
+        %span.gh-form-actions-bar-label{ data: { group_wizard_target: 'nextLabel' } }= t('shared.actions.next')
+        %span.gh-form-actions-bar-label--compact{ data: { group_wizard_target: 'nextLabelShort' } }= t('shared.actions.next')
         %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true',
                                       data: { group_wizard_target: 'nextIcon' } }
-      = f.submit 'Utwórz grupę', class: 'gh-btn', hidden: true,
+      = f.submit t('.submit'), class: 'gh-btn', hidden: true,
         data: { group_wizard_target: 'submit' }
diff --git a/app/views/story_groups/confirm_destroy.html.haml b/app/views/story_groups/confirm_destroy.html.haml
index 54d12d5d..ab3323d7 100644
--- a/app/views/story_groups/confirm_destroy.html.haml
+++ b/app/views/story_groups/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń grupę #{@story_group.name}"
+- content_for :title, t('.page_title', name: @story_group.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/story_groups/created.html.haml b/app/views/story_groups/created.html.haml
index 4f42b3dc..7d933abc 100644
--- a/app/views/story_groups/created.html.haml
+++ b/app/views/story_groups/created.html.haml
@@ -1,47 +1,30 @@
-- content_for :title, "Grupa #{@story_group.name} jest gotowa"
+- content_for :title, t('.page_title', name: @story_group.name)
 - quick = @counts.values.any?(&:positive?)
-- created_list = [gh_plural(@counts[:ranks], 'rangę', 'rangi', 'rang'),
-                  gh_plural(@counts[:badges], 'odznakę', 'odznaki', 'odznak'),
-                  gh_plural(@counts[:items], 'przedmiot', 'przedmioty', 'przedmiotów'),
-                  gh_plural(@counts[:categories], 'kategorię', 'kategorie', 'kategorii')]
-- created_parts = %i[ranks badges items categories].each_with_index.map { |key, i| "#{@counts[key]} #{created_list[i]}" }
-- created_parts[3] = "#{created_parts[3]} w szablonie arkusza"
+- created_parts = %i[ranks badges items categories].map { |key| t(".#{key}", count: @counts[key]) }
 
 %section.gh-panel.gh-wizard-success-panel
   .gh-wizard-success-icon.gh-octagon-clip
     %i.fa-solid.fa-check{ 'aria-hidden': 'true' }
 
-  %h1.gh-h1= "Grupa „#{@story_group.name}” jest gotowa"
+  %h1.gh-h1= t('.title', name: @story_group.name)
 
   %p.gh-lead
     - if quick
-      = "Utworzono #{gh_and_list(created_parts)}."
+      = t('.quick_lead', list: gh_and_list(created_parts))
     - else
-      Grupa jest pusta. Poniżej znajdziesz kolejne kroki.
+      = t('.empty_lead')
 
   %p.gh-explainer-note
     %i.fa-solid.fa-qrcode{ 'aria-hidden': 'true' }
-    %span
-      Kod do dołączenia utworzysz w zakładce
-      %b Zaproszenia
-      \, kiedy będziesz go potrzebować. Możesz mieć kilka kodów naraz,
-      z limitem osób albo datą ważności.
+    %span= t('.invites_note_html', tab: tag.b(t('.invites_tab')))
 
-  %h2.gh-h3 Co dalej
+  %h2.gh-h3= t('.next')
   %ol.gh-next-steps-list
-    - if quick
-      %li Zaproś studentów: pokaż im kod albo kod QR.
-      %li Po pierwszych zajęciach utwórz arkusz ocen i oceń studentów.
-      %li Zajrzyj do sklepu i dopasuj opisy przedmiotów do swojej opowieści.
-    - else
-      %li Dodaj rangi, żeby studenci widzieli, do czego dążą.
-      %li Dodaj przedmioty do sklepu.
-      %li Dodaj odznaki za szczególne osiągnięcia.
-      %li Utwórz szablon arkusza ocen.
-      %li Zaproś studentów: pokaż im kod albo kod QR.
+    - (quick ? t('.quick_steps') : t('.empty_steps')).each do |step|
+      %li= step
 
   .gh-button-row
-    = link_to 'Przejdź do grupy', story_group_path(@story_group), class: 'gh-btn'
+    = link_to t('.go_to_group'), story_group_path(@story_group), class: 'gh-btn'
     = link_to new_story_group_invite_path(@story_group), class: 'gh-btn gh-btn--secondary' do
       %i.fa-solid.fa-qrcode{ 'aria-hidden': 'true' }
-      Utwórz zaproszenie
+      = t('.create_invite')
diff --git a/app/views/story_groups/edit.html.haml b/app/views/story_groups/edit.html.haml
index 688cc398..703f0f6e 100644
--- a/app/views/story_groups/edit.html.haml
+++ b/app/views/story_groups/edit.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, "Ustawienia grupy - #{@story_group.name}"
+- content_for :title, t('.page_title', name: @story_group.name)
 
 = render 'settings', story_group: @story_group
diff --git a/app/views/story_groups/index.html.haml b/app/views/story_groups/index.html.haml
index 56848dc9..670d0d12 100644
--- a/app/views/story_groups/index.html.haml
+++ b/app/views/story_groups/index.html.haml
@@ -1,25 +1,21 @@
-- content_for :title, 'Grupy'
+- content_for :title, t('.title')
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Grupy
-    %p.gh-lead
-      - if @current_user.student?
-        Grupy, w których się uczysz.
-      - else
-        Grupy, które prowadzisz, wspierasz albo w których się uczysz.
+    %h1.gh-h1= t('.title')
+    %p.gh-lead= @current_user.student? ? t('.student_lead') : t('.teacher_lead')
 
   .gh-button-row
     = link_to new_join_path, class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-plus
-      Dołącz do grupy
+      = t('.join')
     - if policy(:story_group).create?
       = link_to new_story_group_path, class: 'gh-btn' do
         %i.fa-solid.fa-plus
-        Utwórz grupę
+        = t('.create')
 
 - if @listing.tabs.size > 1
-  %nav.gh-group-tabs{ 'aria-label': 'Filtr grup' }
+  %nav.gh-group-tabs{ 'aria-label': t('.filter') }
     - @listing.tabs.each do |tab|
       = link_to story_groups_path(filter: tab.key), class: 'gh-group-tab',
         'aria-current': (@listing.filter == tab.key).to_s do
@@ -32,8 +28,8 @@
       %label.gh-search-input.gh-search-input--wide
         %i.fa-solid.fa-magnifying-glass{ 'aria-hidden': 'true' }
         %input{ type: 'search',
-                placeholder: 'Szukaj grupy',
-                'aria-label': 'Szukaj grupy',
+                placeholder: t('.search'),
+                'aria-label': t('.search'),
                 data: { group_search_target: 'input', action: 'input->group-search#filter' } }
 
     .gh-group-index-grid
@@ -42,21 +38,17 @@
 
     %section.gh-panel.gh-empty-state{ hidden: true, data: { group_search_target: 'empty' } }
       %h2.gh-h2
-        Brak grup o nazwie
+        = t('.no_match')
         %span{ data: { group_search_target: 'emptyQuery' } }
-      %p.gh-lead Wyczyść wyszukiwanie albo sprawdź pisownię.
+      %p.gh-lead= t('.no_match_hint')
 
   - else
     %section.gh-panel.gh-empty-state
       %h2.gh-h2
         - if @listing.filter
-          Brak grup w tej zakładce
+          = t('.empty_tab_title')
         - elsif @current_user.student?
-          Nie należysz jeszcze do żadnej grupy
+          = t('.empty_student_title')
         - else
-          Nie masz jeszcze żadnej grupy
-      %p.gh-lead
-        - if @listing.filter
-          Zmień zakładkę, żeby zobaczyć pozostałe grupy.
-        - else
-          Masz kod od prowadzącego? Dołącz do grupy jako uczestnik.
+          = t('.empty_title')
+      %p.gh-lead= @listing.filter ? t('.empty_tab_body') : t('.empty_body')
diff --git a/app/views/story_groups/new.html.haml b/app/views/story_groups/new.html.haml
index 2688b3c1..2fb60530 100644
--- a/app/views/story_groups/new.html.haml
+++ b/app/views/story_groups/new.html.haml
@@ -1,3 +1,3 @@
-- content_for :title, 'Nowa grupa'
+- content_for :title, t('.page_title')
 
 = render 'wizard', story_group: @story_group
diff --git a/app/views/students/_confirm_destroy.html.haml b/app/views/students/_confirm_destroy.html.haml
index 4afeb0da..64229930 100644
--- a/app/views/students/_confirm_destroy.html.haml
+++ b/app/views/students/_confirm_destroy.html.haml
@@ -1,29 +1,26 @@
 - losses = student_removal_losses(sheet)
 
-%h2#gh-kick-title.gh-h2 Usunąć studenta z grupy?
-%p
-  = "#{student.display_name} straci dostęp do grupy"
-  i zniknie z list, rankingu i arkuszy ocen.
+%h2#gh-kick-title.gh-h2= t('.title')
+%p= t('.access_lost', name: student.display_name)
 
 - if losses.any?
   %p.gh-warning-note{ role: 'alert' }
     %i.fa-solid.fa-triangle-exclamation{ 'aria-hidden': 'true' }
     %span
-      = "Przepadną: #{gh_and_list(losses)}."
-      Tego nie da się cofnąć.
+      = t('.losses', list: gh_and_list(losses))
+      = t('.irreversible')
 - else
-  %p.gh-explainer-note Ten student nie ma jeszcze odznak, przedmiotów ani historii waluty.
+  %p.gh-explainer-note= t('.nothing_to_lose')
 
-%p.gh-small
-  Jeśli wróci do grupy, dostanie nowe konto uczestnika i zacznie od zera.
+%p.gh-small= t('.rejoin_note')
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', story_group_student_path(@story_group, student), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), story_group_student_path(@story_group, student), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń z grupy', story_group_student_path(@story_group, student),
+  = button_to t('.remove'), story_group_student_path(@story_group, student),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal2' : nil) } }
diff --git a/app/views/students/_form.html.haml b/app/views/students/_form.html.haml
index 818de023..78df4f81 100644
--- a/app/views/students/_form.html.haml
+++ b/app/views/students/_form.html.haml
@@ -7,30 +7,28 @@
           turbo_frame: (@in_modal ? 'modal' : nil),
           lives_stepper_start_value: lives } do |f|
 
-  %h2#gh-student-title.gh-h2 Edytuj studenta
+  %h2#gh-student-title.gh-h2= t('.title')
   %p
     = "#{student.display_name}."
-    Imię, nazwisko i e-mail pochodzą z konta studenta.
+    = t('.account_note')
 
   .gh-form-field
-    %p#gh-lives-label.gh-form-label Życia
+    %p#gh-lives-label.gh-form-label= t('.lives')
     .gh-number-stepper{ role: 'group', 'aria-labelledby': 'gh-lives-label' }
-      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Odbierz życie',
+      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('.take_life'),
                           disabled: lives.zero?,
                           data: { lives_stepper_target: 'down',
                                   action: 'lives-stepper#down' } }
         %i.fa-solid.fa-minus{ 'aria-hidden': 'true' }
       %output{ 'aria-live': 'polite', data: { lives_stepper_target: 'output' } }= lives
-      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': 'Dodaj życie',
+      %button.gh-number-stepper-button.gh-octagon-clip{ type: 'button', 'aria-label': t('.add_life'),
                           data: { lives_stepper_target: 'up',
                                   action: 'lives-stepper#up' } }
         %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
 
     = f.hidden_field :lives, value: lives, data: { lives_stepper_target: 'field' }
 
-    %span.gh-field-hint
-      Życie odbierasz za nieusprawiedliwioną nieobecność. Przy 0 życiach
-      student kupi tylko przedmioty dostępne przy 0 życiach.
+    %span.gh-field-hint= t('.lives_hint')
 
   - if error
     %p.gh-field-error{ role: 'alert' }
@@ -38,19 +36,17 @@
       %span= error
 
   .gh-form-section.gh-form-section--divider
-    %p.gh-form-label Usuń z grupy
-    %p.gh-small
-      Student straci dostęp do grupy, a jego odznaki, przedmioty i historia
-      waluty przepadną. Dołączy ponownie tylko z nowym kodem.
+    %p.gh-form-label= t('.remove_label')
+    %p.gh-small= t('.remove_hint')
     = link_to confirm_destroy_story_group_student_path(@story_group, student),
       class: 'gh-btn gh-btn--secondary gh-btn--small gh-remove-student-btn',
       data: { turbo_frame: 'modal2' } do
       %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-      Usuń z grupy
+      = t('.remove')
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
     - else
-      = link_to 'Anuluj', story_group_student_path(@story_group, student), class: 'gh-btn gh-btn--secondary'
-    %button.gh-btn{ type: 'submit', data: { lives_stepper_target: 'submit' } } Zapisz
+      = link_to t('shared.actions.cancel'), story_group_student_path(@story_group, student), class: 'gh-btn gh-btn--secondary'
+    %button.gh-btn{ type: 'submit', data: { lives_stepper_target: 'submit' } }= t('shared.actions.save')
diff --git a/app/views/students/_row.html.haml b/app/views/students/_row.html.haml
index 0fef06f5..7c50a873 100644
--- a/app/views/students/_row.html.haml
+++ b/app/views/students/_row.html.haml
@@ -13,17 +13,17 @@
       %small= student_list_subtitle(student)
 
   %span
-    %span.gh-mobile-field-label Ranga
+    %span.gh-mobile-field-label= t('.rank')
     %span.gh-student-rank-cell= row.rank&.name || '—'
 
   %span
-    %span.gh-mobile-field-label Życia
+    %span.gh-mobile-field-label= t('.lives')
     .gh-lives-control
       = button_to update_lives_story_group_student_path(@story_group, student, change: -1),
         method: :post, class: 'gh-number-stepper-button gh-number-stepper-button--sm gh-octagon-clip',
         disabled: lives.zero?,
-        form: { 'aria-label': "Odbierz życie: #{name}" },
-        'aria-label': "Odbierz życie: #{name}" do
+        form: { 'aria-label': t('.take_life', name: name) },
+        'aria-label': t('.take_life', name: name) do
         %i.fa-solid.fa-minus{ 'aria-hidden': 'true' }
 
       %span.gh-lives-badge{ class: ('gh-lives-badge--zero' if lives.zero?) }
@@ -32,34 +32,34 @@
 
       = button_to update_lives_story_group_student_path(@story_group, student, change: 1),
         method: :post, class: 'gh-number-stepper-button gh-number-stepper-button--sm gh-octagon-clip',
-        form: { 'aria-label': "Dodaj życie: #{name}" },
-        'aria-label': "Dodaj życie: #{name}" do
+        form: { 'aria-label': t('.add_life', name: name) },
+        'aria-label': t('.add_life', name: name) do
         %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
 
   %span
-    %span.gh-mobile-field-label Do wydania
+    %span.gh-mobile-field-label= t('.balance')
     %span.gh-numeric-cell= student.current_currency.to_i
   %span
-    %span.gh-mobile-field-label Zebrane
+    %span.gh-mobile-field-label= t('.total')
     %span.gh-numeric-cell= student.total_currency.to_i
   %span
-    %span.gh-mobile-field-label Odznaki
+    %span.gh-mobile-field-label= t('.badges')
     %span.gh-numeric-cell= row.badge_count
 
   .gh-student-actions-cell
     = link_to new_story_group_student_badge_path(@story_group, student),
-      class: 'gh-icon-button', title: 'Przyznaj odznakę',
-      'aria-label': "Przyznaj odznakę: #{name}",
+      class: 'gh-icon-button', title: t('.award_badge'),
+      'aria-label': t('.award_badge_for', name: name),
       data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-award{ 'aria-hidden': 'true' }
 
     = link_to new_story_group_student_currency_adjustment_path(@story_group, student),
-      class: 'gh-icon-button', title: 'Koryguj walutę',
-      'aria-label': "Koryguj walutę: #{name}",
+      class: 'gh-icon-button', title: t('.adjust_currency'),
+      'aria-label': t('.adjust_currency_for', name: name),
       data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-coins{ 'aria-hidden': 'true' }
 
     = link_to story_group_student_path(@story_group, student, tab: 'hist'),
-      class: 'gh-icon-button', title: 'Historia transakcji',
-      'aria-label': "Historia: #{name}" do
+      class: 'gh-icon-button', title: t('.history'),
+      'aria-label': t('.history_for', name: name) do
       %i.fa-solid.fa-clock-rotate-left{ 'aria-hidden': 'true' }
diff --git a/app/views/students/_tab_badges.html.haml b/app/views/students/_tab_badges.html.haml
index 35c32de8..0ac06b29 100644
--- a/app/views/students/_tab_badges.html.haml
+++ b/app/views/students/_tab_badges.html.haml
@@ -15,18 +15,18 @@
               - if (discount = badge_discount_label(badge))
                 %span.gh-tag.gh-tag--discount= discount
               - if badge.deleted?
-                %span.gh-tag.gh-tag--removed Usunięta z listy
+                %span.gh-tag.gh-tag--removed= t('.removed')
 
             %p.gh-rule-text= badge.didactic_description
             - if badge.story_description.present?
               %p.gh-card-flavor= badge.story_description
 
             .gh-card-footer
-              %span.gh-card-meta= "Przyznana #{gh_when(students_badge.created_at)}"
-              = link_to 'Odbierz',
+              %span.gh-card-meta= t('.awarded', when: gh_when(students_badge.created_at))
+              = link_to t('.revoke'),
                 confirm_destroy_story_group_student_badge_path(@story_group, sheet.student, students_badge),
                 class: 'gh-link-button',
-                'aria-label': "Odbierz odznakę #{badge.name}",
+                'aria-label': t('.revoke_label', name: badge.name),
                 data: { turbo_frame: 'modal' }
 - else
-  %p.gh-explainer-note Student nie ma jeszcze żadnej odznaki.
+  %p.gh-explainer-note= t('.empty')
diff --git a/app/views/students/_tab_history.html.haml b/app/views/students/_tab_history.html.haml
index 891e8808..cab77949 100644
--- a/app/views/students/_tab_history.html.haml
+++ b/app/views/students/_tab_history.html.haml
@@ -3,4 +3,4 @@
 = render 'currency_transactions/ledger', ledger: sheet.ledger, kind: kind,
   path_for: path_for,
   summary: ledger_summary_sentence(sheet.ledger),
-  empty_message: 'Brak wpisów tego typu.'
+  empty_message: t('.empty')
diff --git a/app/views/students/_tab_items.html.haml b/app/views/students/_tab_items.html.haml
index affd262c..e45e2150 100644
--- a/app/views/students/_tab_items.html.haml
+++ b/app/views/students/_tab_items.html.haml
@@ -1,6 +1,4 @@
-%p.gh-small.gh-tab-panel-intro
-  Przedmioty kupione w sklepie. Wykorzystanie przedmiotu (np. poprawę
-  wejściówki) rozliczasz na zajęciach.
+%p.gh-small.gh-tab-panel-intro= t('.intro')
 
 - if sheet.purchases.any?
   .gh-item-list
@@ -8,6 +6,4 @@
       = render 'students_items/card', purchase: purchase, cost: true,
         foot: purchase_teacher_line(purchase)
 - else
-  %p.gh-explainer-note
-    Student nic jeszcze nie kupił. Przedmioty pojawią się tu razem z ceną,
-    jaką zapłacił.
+  %p.gh-explainer-note= t('.empty')
diff --git a/app/views/students/confirm_destroy.html.haml b/app/views/students/confirm_destroy.html.haml
index df74ff73..2413e968 100644
--- a/app/views/students/confirm_destroy.html.haml
+++ b/app/views/students/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usuń z grupy - #{@student.display_name}"
+- content_for :title, t('.page_title', name: @student.display_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal2' do
diff --git a/app/views/students/edit.html.haml b/app/views/students/edit.html.haml
index b1dac198..2d08d7e2 100644
--- a/app/views/students/edit.html.haml
+++ b/app/views/students/edit.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Edytuj studenta - #{@student.display_name}"
+- content_for :title, t('.page_title', name: @student.display_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/students/index.html.haml b/app/views/students/index.html.haml
index 6e10c9f7..3740ee37 100644
--- a/app/views/students/index.html.haml
+++ b/app/views/students/index.html.haml
@@ -1,60 +1,58 @@
-- content_for :title, 'Studenci'
+- content_for :title, t('.title')
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Studenci
+    %h1.gh-h1= t('.title')
     %p.gh-lead= student_list_lead(@list)
 
   .gh-button-row
     = link_to story_group_invites_path(@story_group), class: 'gh-btn gh-btn--secondary' do
       %i.fa-solid.fa-qrcode{ 'aria-hidden': 'true' }
-      Kody i zaproszenia
+      = t('.invites')
     = link_to quick_story_group_invites_path(@story_group), class: 'gh-btn',
                                                             data:  { turbo_frame: 'modal' } do
       %i.fa-solid.fa-eye{ 'aria-hidden': 'true' }
-      Pokaż kod dla studentów
+      = t('.show_code')
 
 - if @list.any?
   %div{data: { controller:              'list-search',
                list_search_total_value: @list.size,
-               list_search_of_value:    'z',  }}
+               list_search_of_value:    t('.of'),  }}
     .gh-student-list-toolbar
       %label.gh-search-input
         %i.fa-solid.fa-magnifying-glass{ 'aria-hidden': 'true' }
         %input{type:         'search',
-               placeholder:  'Szukaj studenta',
-               'aria-label': 'Szukaj studenta',
+               placeholder:  t('.search'),
+               'aria-label': t('.search'),
                data:         { list_search_target: 'input', action: 'input->list-search#filter' },}
       %span.gh-card-meta{ data: { list_search_target: 'count' } }
-        = "#{@list.size} z #{@list.size}"
+        = t('.count', shown: @list.size, total: @list.size)
 
     %section.gh-panel.gh-student-list-panel
       %ul.gh-student-rows{ role: 'list' }
         %li.gh-student-row.gh-student-row--header{ 'aria-hidden': 'true' }
-          %span Student
-          %span Ranga
-          %span Życia
-          %span Do wydania
-          %span Zebrane
-          %span Odznaki
-          %span.gh-ledger-cell--right Akcje
+          %span= t('.columns.student')
+          %span= t('.columns.rank')
+          %span= t('.columns.lives')
+          %span= t('.columns.balance')
+          %span= t('.columns.total')
+          %span= t('.columns.badges')
+          %span.gh-ledger-cell--right= t('.columns.actions')
 
         = render partial: 'students/row', collection: @list.rows, as: :row
 
     %section.gh-panel.gh-empty-state{ hidden: true, data: { list_search_target: 'empty' } }
       %h2.gh-h2
-        Brak studentów o nazwie
+        = t('.no_match')
         %span{ data: { list_search_target: 'emptyQuery' } }
-      %p.gh-lead Wyczyść wyszukiwanie albo sprawdź pisownię.
+      %p.gh-lead= t('.no_match_hint')
 - else
   %section.gh-panel.gh-empty-state
-    %h2.gh-h2 Nie ma jeszcze nikogo w grupie
-    %p.gh-lead
-      Wyślij studentom kod albo zaproszenie — kiedy dołączą, pojawią się tutaj
-      razem z rangą, walutą i życiami.
+    %h2.gh-h2= t('.empty_title')
+    %p.gh-lead= t('.empty_body')
     .gh-button-row
-      = link_to 'Kody i zaproszenia', story_group_invites_path(@story_group), class: 'gh-btn'
+      = link_to t('.invites'), story_group_invites_path(@story_group), class: 'gh-btn'
       = link_to quick_story_group_invites_path(@story_group), class: 'gh-btn gh-btn--secondary',
                                                               data:  { turbo_frame: 'modal' } do
         %i.fa-solid.fa-eye{ 'aria-hidden': 'true' }
-        Pokaż kod dla studentów
+        = t('.show_code')
diff --git a/app/views/students/show.html.haml b/app/views/students/show.html.haml
index 4da24aeb..3394ceea 100644
--- a/app/views/students/show.html.haml
+++ b/app/views/students/show.html.haml
@@ -6,7 +6,7 @@
     %span.gh-avatar.gh-octagon-clip{ 'data-gh-h': gh_avatar_hue(name), 'aria-hidden': 'true' }= gh_initials(name)
     %div
       %p.gh-breadcrumbs
-        = link_to 'Studenci', story_group_students_path(@story_group)
+        = link_to t('.breadcrumb'), story_group_students_path(@story_group)
         %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
         %span= name
       %h1.gh-h1= name
@@ -16,19 +16,19 @@
       = link_to new_story_group_student_badge_path(@story_group, @student), class: 'gh-btn',
         data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-award{ 'aria-hidden': 'true' }
-        Przyznaj odznakę
+        = t('.award_badge')
       = link_to new_story_group_student_currency_adjustment_path(@story_group, @student),
         class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-coins{ 'aria-hidden': 'true' }
-        Koryguj walutę
+        = t('.adjust_currency')
       = link_to edit_story_group_student_path(@story_group, @student),
         class: 'gh-btn gh-btn--secondary', data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-pen{ 'aria-hidden': 'true' }
-        Edytuj
+        = t('shared.actions.edit')
 
   %dl.gh-student-stats
     .gh-student-stat
-      %dt Ranga
+      %dt= t('.rank')
       %dd
         = @sheet.rank&.name || '—'
         - if (line = student_rank_progress_line(@sheet))
@@ -36,27 +36,27 @@
       - if (progress = @sheet.rank_progress)
         .gh-progress-bar.gh-octagon-clip{ role: 'progressbar', 'aria-valuemin': 0, 'aria-valuemax': 100,
                  'aria-valuenow': progress,
-                 'aria-label': "Postęp do rangi #{@sheet.next_rank.name}" }
+                 'aria-label': t('.rank_progress_label', rank: @sheet.next_rank.name) }
           %i.gh-octagon-clip{ style: "--gh-p: #{progress}%" }
 
     .gh-student-stat
-      %dt Do wydania
+      %dt= t('.balance')
       %dd= @sheet.balance
     .gh-student-stat
-      %dt Zebrane łącznie
+      %dt= t('.total')
       %dd= @sheet.total
     .gh-student-stat
-      %dt Życia
+      %dt= t('.lives')
       %dd
         %span.gh-lives-badge{ class: ('gh-lives-badge--zero' if @sheet.lives.zero?) }
           %i.fa-solid.fa-heart{ 'aria-hidden': 'true' }
         = @sheet.lives
 
-%nav.gh-group-tabs{ 'aria-label': 'Sekcje studenta' }
-  - StudentSheet::TABS.each do |key, label|
+%nav.gh-group-tabs{ 'aria-label': t('.sections') }
+  - StudentSheet::TABS.each do |key|
     = link_to story_group_student_path(@story_group, @student, tab: key), class: 'gh-group-tab',
       'aria-current': (@tab == key).to_s do
-      = label
+      = t(".tabs.#{key}")
       %span.gh-count-label= @sheet.count_for(key)
 
 %section.gh-panel.gh-tab-panel
diff --git a/app/views/students_activity_group_categories/_review_dialog.html.haml b/app/views/students_activity_group_categories/_review_dialog.html.haml
index 1d6eed95..18e18729 100644
--- a/app/views/students_activity_group_categories/_review_dialog.html.haml
+++ b/app/views/students_activity_group_categories/_review_dialog.html.haml
@@ -3,14 +3,14 @@
                                              action: 'close->grading#closeReview click->grading#closeOnBackdrop' } }
   .gh-dialog-body.gh-octagon-clip
     %h2#gh-review-title.gh-h2
-      Przyznajesz
+      = t('.awarding')
       %span{ data: { grading_target: 'reviewSum' } }
       = @story_group.currency_name
       %span{ data: { grading_target: 'reviewStudents' } }
 
     %p.gh-warning-note{ role: 'alert' }
       %i.fa-solid.fa-lock{ 'aria-hidden': 'true' }
-      Po zatwierdzeniu nie da się tego cofnąć. Sprawdź listę, zanim przyznasz nagrody.
+      = t('.warning')
 
     %ul.gh-review-list
       - students.each do |student|
@@ -34,8 +34,8 @@
     .gh-dialog-button-row
       %button.gh-btn.gh-btn--secondary{ type: 'button', autofocus: true,
                                   data: { action: 'grading#closeReview' } }
-        Wróć do edycji
+        = t('shared.actions.back_to_editing')
       %button.gh-btn.gh-btn--gold{ type: 'submit', form: 'gh-grade-form' }
-        Przyznaj
+        = t('.confirm')
         %span{ data: { grading_target: 'reviewConfirmSum' } }
         = @story_group.currency_name
diff --git a/app/views/students_activity_group_categories/edit.html.haml b/app/views/students_activity_group_categories/edit.html.haml
index dc795a66..b897f0e8 100644
--- a/app/views/students_activity_group_categories/edit.html.haml
+++ b/app/views/students_activity_group_categories/edit.html.haml
@@ -3,46 +3,37 @@
 - students   = @sheet.students
 - template   = @activity_group.activity_group_template
 
-- grid_data = { controller: 'grading',
-                grading_cells_value: %w[pole pola pól].to_json,
-                grading_students_value: %w[studenta studentów studentów].to_json,
-                grading_recipients_value: %w[studentowi studentom studentom].to_json,
-                grading_states_value: %w[puste zaznaczone przyznane].to_json,
-                grading_currency_value: @story_group.currency_name.to_s,
-                grading_award_label_value: 'Przyznaj' }
+- grid_data = { controller: 'grading', grading_i18n_value: t('.js').to_json }
 
 .gh-grading-screen{ data: grid_data }
   %section.gh-panel.gh-page-header.gh-grading-head
     .gh-page-header-text
       %p.gh-breadcrumbs
-        = link_to 'Arkusze ocen', story_group_activity_groups_path(@story_group)
+        = link_to t('layouts.navigation.sheets'), story_group_activity_groups_path(@story_group)
         %i.fa-solid.fa-chevron-right{ 'aria-hidden': 'true' }
         %span= template.base_name
       %h1.gh-h1= @activity_group.name
-      %p.gh-lead
-        = "#{categories.size} #{gh_plural(categories.size, 'kategoria', 'kategorie', 'kategorii')},"
-        = "#{students.size} #{gh_plural(students.size, 'student', 'studentów', 'studentów')}."
-        Zaznacz, kto zdobył nagrody, a przed przyznaniem przejrzysz wszystko jeszcze raz.
+      %p.gh-lead= t('.lead', categories: t('.categories', count: categories.size), count: students.size)
 
     .gh-grading-head-actions
       %label.gh-search-input
         %i.fa-solid.fa-magnifying-glass{ 'aria-hidden': 'true' }
-        = search_field_tag :student_search, nil, placeholder: 'Szukaj studenta',
-          'aria-label': 'Szukaj studenta',
+        = search_field_tag :student_search, nil, placeholder: t('.search'),
+          'aria-label': t('.search'),
           data: { grading_target: 'search', action: 'input->grading#filter' }
 
-      %ul.gh-cell-legend{ 'aria-label': 'Legenda' }
+      %ul.gh-cell-legend{ 'aria-label': t('.legend') }
         %li
           %span.gh-grading-cell.gh-grading-cell--sm{ 'aria-hidden': 'true' }
-          Puste
+          = t('.empty')
         %li
           %span.gh-grading-cell.gh-grading-cell--sm.gh-grading-cell--pending{ 'aria-hidden': 'true' }
             %i.fa-solid.fa-check
-          Zaznaczone teraz
+          = t('.marked_now')
         %li
           %span.gh-grading-cell.gh-grading-cell--sm.gh-grading-cell--awarded{ 'aria-hidden': 'true' }
             %i.fa-solid.fa-check
-          Przyznane, nie do cofnięcia
+          = t('.awarded_locked')
 
   - if @sheet.gradeable?
     = form_with url: story_group_activity_group_students_activity_group_categories_path(@story_group, @activity_group), method: :patch, id: 'gh-grade-form', class: 'gh-grading-form' do
@@ -51,7 +42,7 @@
           %table.gh-grading-table
             %thead
               %tr
-                %th.gh-grading-th-student{ scope: 'col' } Student
+                %th.gh-grading-th-student{ scope: 'col' }= t('.student')
                 - categories.each do |category|
                   %th{ scope: 'col' }
                     .gh-grading-column-head
@@ -60,12 +51,12 @@
                       %span.gh-price-badge
                         %b= "+#{category.reward.to_i}"
                         = render 'layouts/currency_token', story_group: @story_group, size: 16
-                      %button.gh-grading-column-select-all{ type: 'button', title: 'Zaznacz całą kolumnę',
+                      %button.gh-grading-column-select-all{ type: 'button', title: t('.select_column'),
                                          data: { action: 'grading#toggleColumn',
                                                  grading_column_param: category.id } }
                         %i.fa-solid.fa-check-double{ 'aria-hidden': 'true' }
-                        Wszyscy
-                %th.gh-grading-th-total{ scope: 'col' } Razem
+                        = t('.everyone')
+                %th.gh-grading-th-total{ scope: 'col' }= t('.total')
 
             %tbody
               - students.each do |student|
@@ -79,13 +70,14 @@
                       = name
 
                   - categories.each do |category|
+                    - label = "#{name}, #{category.didactic_description}"
                     %td
                       - if @sheet.awarded?(student, category)
                         - fresh = @awarded_pairs.include?([category.id, student.id])
                         %span.gh-grading-cell.gh-grading-cell--awarded{ class: ('gh-grading-cell--stamp' if fresh),
-                                                        title: 'Przyznane, nie można cofnąć',
+                                                        title: t('.locked_title'),
                                                         role: 'img',
-                                                        'aria-label': "#{name}, #{category.didactic_description}: przyznane",
+                                                        'aria-label': t('.cell_awarded', label: label),
                                                         data: { action: 'click->grading#locked' } }
                           %i.fa-solid.fa-check{ 'aria-hidden': 'true' }
                           %i.fa-solid.fa-lock.gh-grading-cell-lock-icon{ 'aria-hidden': 'true' }
@@ -95,9 +87,9 @@
                                                 grading_column: category.id } }
                           = check_box_tag "completions[#{student.id}][#{category.id}]", '1', false,
                             id: nil,
-                            'aria-label': "#{name}, #{category.didactic_description}: puste",
+                            'aria-label': t('.cell_empty', label: label),
                             data: { action: 'grading#toggle',
-                                    gh_label: "#{name}, #{category.didactic_description}" }
+                                    gh_label: label }
                           %i.fa-solid.fa-check{ 'aria-hidden': 'true' }
 
                   %td.gh-grading-td-total
@@ -106,8 +98,7 @@
 
       %section.gh-panel.gh-action-bar{ 'aria-live': 'polite' }
         %p.gh-action-bar-text
-          %span{ data: { grading_target: 'barEmpty' } }
-            Nic nie jest zaznaczone. Kliknij pola studentów, którzy zdobyli nagrody.
+          %span{ data: { grading_target: 'barEmpty' } }= t('.nothing_marked')
           %span{ hidden: true, data: { grading_target: 'barActive' } }
             %b{ data: { grading_target: 'barCells' } }
             %span{ data: { grading_target: 'barStudents' } }
@@ -118,39 +109,33 @@
         .gh-action-bar-buttons
           %button.gh-btn.gh-btn--secondary{ type: 'button', hidden: true,
                                       data: { grading_target: 'clear', action: 'grading#clear' } }
-            Wyczyść zaznaczenia
+            = t('.clear')
           %button.gh-btn{ type: 'submit',
                           data: { grading_target: 'submit', action: 'grading#review' } }
-            Przejrzyj i przyznaj
+            = t('.review')
 
     = render 'review_dialog', categories: categories, students: students
 
   - elsif categories.empty?
     %section.gh-panel.gh-empty-state
-      %h2.gh-h2 Ten arkusz nie ma żadnej kolumny
-      %p.gh-lead
-        Dodaj kolumny w ustawieniach arkusza, żeby było za co nagradzać.
+      %h2.gh-h2= t('.no_columns_title')
+      %p.gh-lead= t('.no_columns_body')
       .gh-button-row
-        = link_to 'Ustawienia arkusza', edit_story_group_activity_group_path(@story_group, @activity_group),
+        = link_to t('.sheet_settings'), edit_story_group_activity_group_path(@story_group, @activity_group),
           class: 'gh-btn'
   - else
     %section.gh-panel.gh-empty-state
-      %h2.gh-h2 W tej grupie nie ma jeszcze studentów
-      %p.gh-lead
-        Zaproś studentów do grupy — arkusz czeka gotowy i nic w nim nie przepada.
+      %h2.gh-h2= t('.no_students_title')
+      %p.gh-lead= t('.no_students_body')
       .gh-button-row
-        = link_to 'Zaproszenia', story_group_invites_path(@story_group), class: 'gh-btn'
+        = link_to t('.invites'), story_group_invites_path(@story_group), class: 'gh-btn'
 
 .gh-grading-mobile-fallback
   %section.gh-panel.gh-grading-mobile-panel
     .gh-grading-mobile-icon.gh-octagon-clip
       %i.fa-solid.fa-desktop{ 'aria-hidden': 'true' }
     %h1.gh-h2= @activity_group.name
-    %p.gh-lead
-      Ocenianie w tabeli działa na komputerze. Ta tabela ma
-      = "#{categories.size} #{gh_plural(categories.size, 'kategorię', 'kategorie', 'kategorii')}"
-      i
-      = "#{students.size} #{gh_plural(students.size, 'studenta', 'studentów', 'studentów')},"
-      więc na telefonie byłaby nieczytelna.
-    %p.gh-small Na telefonie sprawdzisz ostatnie zakupy i powiadomienia.
-    = link_to 'Wróć na start', root_path, class: 'gh-btn gh-btn--secondary'
+    %p.gh-lead= t('.mobile_body', categories: t('.mobile_categories', count: categories.size),
+                                  students:   t('.mobile_students', count: students.size))
+    %p.gh-small= t('.mobile_hint')
+    = link_to t('.back_home'), root_path, class: 'gh-btn gh-btn--secondary'
diff --git a/app/views/students_badges/_confirm_destroy.html.haml b/app/views/students_badges/_confirm_destroy.html.haml
index 01b73249..f3eaea22 100644
--- a/app/views/students_badges/_confirm_destroy.html.haml
+++ b/app/views/students_badges/_confirm_destroy.html.haml
@@ -1,16 +1,16 @@
 - badge = students_badge.badge
 
-%h2#gh-revoke-title.gh-h2= "Odebrać odznakę „#{badge.name}”?"
+%h2#gh-revoke-title.gh-h2= t('.title', name: badge.name)
 %p= badge_revoke_sentence(@student, badge)
 
 .gh-dialog-button-row
   - if @in_modal
     %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }
-      Anuluj
+      = t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', story_group_student_path(@story_group, @student), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), story_group_student_path(@story_group, @student), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Odbierz odznakę',
+  = button_to t('.revoke'),
     story_group_student_badge_path(@story_group, @student, students_badge),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/students_badges/_form.html.haml b/app/views/students_badges/_form.html.haml
index 2066309d..961619ef 100644
--- a/app/views/students_badges/_form.html.haml
+++ b/app/views/students_badges/_form.html.haml
@@ -5,16 +5,16 @@
   method: :post, scope: :students_badge,
   data: { controller: 'badge-picker',
           turbo_frame: (@in_modal ? 'modal' : nil),
-          badge_picker_pick_value: 'Przyznaj',
-          badge_picker_blank_value: 'Wybierz odznakę', } do |f|
+          badge_picker_pick_value: t('.pick'),
+          badge_picker_blank_value: t('.blank'), } do |f|
 
-  %h2#gh-assign-title.gh-h2 Przyznaj odznakę
+  %h2#gh-assign-title.gh-h2= t('.title')
   %p= badge_assign_lead(@student, held, @badges.size)
 
   - if @badges.any?
     %label.gh-search-input.gh-search--full-width
       %i.fa-solid.fa-magnifying-glass{ 'aria-hidden': 'true' }
-      %input{ type: 'search', placeholder: 'Szukaj odznaki', 'aria-label': 'Szukaj odznaki',
+      %input{ type: 'search', placeholder: t('.search'), 'aria-label': t('.search'),
               data: { badge_picker_target: 'input', action: 'input->badge-picker#filter' } }
 
     %ul.gh-badge-picker-list
@@ -38,12 +38,9 @@
                                     badge_picker_for: badge.id } }
         = badge_effect_sentence(badge)
 
-    %p.gh-explainer-note{ hidden: true, data: { badge_picker_target: 'empty' } }
-      Brak odznak o tej nazwie.
+    %p.gh-explainer-note{ hidden: true, data: { badge_picker_target: 'empty' } }= t('.no_match')
   - else
-    %p.gh-explainer-note
-      W tej grupie nie ma jeszcze odznak. Dodaj je w zakładce Odznaki, a potem
-      wróć tutaj.
+    %p.gh-explainer-note= t('.empty')
 
   - if error
     %p.gh-field-error{ role: 'alert' }
@@ -52,9 +49,9 @@
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Anuluj
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.cancel')
     - else
-      = link_to 'Anuluj', story_group_student_path(@story_group, @student), class: 'gh-btn gh-btn--secondary'
+      = link_to t('shared.actions.cancel'), story_group_student_path(@story_group, @student), class: 'gh-btn gh-btn--secondary'
     %button.gh-btn{ type: 'submit', disabled: @badges.empty?,
                     data: { badge_picker_target: 'submit' } }
-      Wybierz odznakę
+      = t('.submit')
diff --git a/app/views/students_badges/confirm_destroy.html.haml b/app/views/students_badges/confirm_destroy.html.haml
index bf0792f9..ac2a0faa 100644
--- a/app/views/students_badges/confirm_destroy.html.haml
+++ b/app/views/students_badges/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Odbierz odznakę #{@students_badge.name}"
+- content_for :title, t('.page_title', name: @students_badge.name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/students_badges/new.html.haml b/app/views/students_badges/new.html.haml
index ddc13389..6b6a19df 100644
--- a/app/views/students_badges/new.html.haml
+++ b/app/views/students_badges/new.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Przyznaj odznakę - #{@student.display_name}"
+- content_for :title, t('.page_title', name: @student.display_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/students_items/_card.html.haml b/app/views/students_items/_card.html.haml
index 7c67a249..fecc4f0a 100644
--- a/app/views/students_items/_card.html.haml
+++ b/app/views/students_items/_card.html.haml
@@ -16,7 +16,7 @@
 
       - if item.deleted?
         .gh-card-tags
-          %span.gh-tag.gh-tag--removed Usunięty z oferty
+          %span.gh-tag.gh-tag--removed= t('.removed')
 
       %p.gh-rule-text= item.didactic_description
       - if item.story_description.present?
diff --git a/app/views/students_items/index.html.haml b/app/views/students_items/index.html.haml
index cc32d236..dd1bd048 100644
--- a/app/views/students_items/index.html.haml
+++ b/app/views/students_items/index.html.haml
@@ -1,4 +1,4 @@
-- title = @own_items ? 'Moje przedmioty' : "Przedmioty — #{@student.display_name}"
+- title = @own_items ? t('.own_title') : t('.title', name: @student.display_name)
 - content_for :title, title
 - count = @purchases.size
 
@@ -9,14 +9,13 @@
       - if @own_items
         = inventory_lead(count)
       - else
-        = "#{count} #{gh_plural(count, 'przedmiot', 'przedmioty', 'przedmiotów')}."
-        Wykorzystanie przedmiotu student rozlicza z Tobą na zajęciach.
+        = t('.teacher_lead', count: count)
 
   - if @own_items
     .gh-button-row
       = link_to story_group_shop_index_path(@story_group), class: 'gh-btn gh-btn--secondary' do
         %i.fa-solid.fa-bag-shopping{ 'aria-hidden': 'true' }
-        Przejdź do sklepu
+        = t('.go_to_shop')
 
 - if @purchases.any?
   .gh-inventory-grid
@@ -27,17 +26,14 @@
     - if @shop
       .gh-panel.gh-empty-slot-panel
         %p= inventory_shop_line(@shop.affordable)
-        = link_to 'Zobacz sklep', story_group_shop_index_path(@story_group), class: 'gh-btn gh-btn--secondary'
+        = link_to t('.see_shop'), story_group_shop_index_path(@story_group), class: 'gh-btn gh-btn--secondary'
 - else
   %section.gh-panel.gh-empty-state
     - if @own_items
-      %h2.gh-h2 Nie masz jeszcze żadnego przedmiotu
-      %p.gh-lead
-        Zbieraj walutę na zajęciach i wydaj ją w sklepie — kupione przedmioty
-        zostaną tutaj razem z datą zakupu.
+      %h2.gh-h2= t('.own_empty_title')
+      %p.gh-lead= t('.own_empty_body')
       .gh-button-row
-        = link_to 'Przejdź do sklepu', story_group_shop_index_path(@story_group), class: 'gh-btn'
+        = link_to t('.go_to_shop'), story_group_shop_index_path(@story_group), class: 'gh-btn'
     - else
-      %h2.gh-h2 Student nic jeszcze nie kupił
-      %p.gh-lead
-        Przedmioty pojawią się tu razem z ceną, jaką zapłacił, i datą zakupu.
+      %h2.gh-h2= t('.empty_title')
+      %p.gh-lead= t('.empty_body')
diff --git a/app/views/teachers/_confirm_destroy.html.haml b/app/views/teachers/_confirm_destroy.html.haml
index 28240657..c0455b09 100644
--- a/app/views/teachers/_confirm_destroy.html.haml
+++ b/app/views/teachers/_confirm_destroy.html.haml
@@ -1,14 +1,12 @@
-- name = teacher.full_name
-
-%h2#gh-del-title.gh-h2= "Usunąć #{name} z grupy?"
-%p Straci dostęp do grupy. Nagrody, które przyznał, zostają u studentów.
+%h2#gh-del-title.gh-h2= t('.title', name: teacher.full_name)
+%p= t('.body')
 
 .gh-dialog-button-row
   - if @in_modal
-    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true } Anuluj
+    %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' }, autofocus: true }= t('shared.actions.cancel')
   - else
-    = link_to 'Anuluj', story_group_teachers_path(@story_group), class: 'gh-btn gh-btn--secondary'
+    = link_to t('shared.actions.cancel'), story_group_teachers_path(@story_group), class: 'gh-btn gh-btn--secondary'
 
-  = button_to 'Usuń z grupy', story_group_teacher_path(@story_group, teacher),
+  = button_to t('.remove'), story_group_teacher_path(@story_group, teacher),
     method: :delete, class: 'gh-btn',
     form: { data: { turbo_frame: (@in_modal ? 'modal' : nil) } }
diff --git a/app/views/teachers/_form.html.haml b/app/views/teachers/_form.html.haml
index 38303d3b..423ac565 100644
--- a/app/views/teachers/_form.html.haml
+++ b/app/views/teachers/_form.html.haml
@@ -5,20 +5,17 @@
           turbo_frame: (@in_modal ? 'modal' : nil),
           teacher_picker_min_value: 2,
           teacher_picker_max_value: 8,
-          teacher_picker_one_value: 'wynik',
-          teacher_picker_few_value: 'wyniki',
-          teacher_picker_many_value: 'wyników',
-          teacher_picker_overflow_value: ', pokazujemy 8 pierwszych', } do
+          teacher_picker_i18n_value: t('.js').to_json, } do
 
-  %h2#gh-add-teacher-title.gh-h2 Dodaj nauczyciela
-  %p Nauczyciel dostanie dostęp do grupy od razu po dodaniu.
+  %h2#gh-add-teacher-title.gh-h2= t('.title')
+  %p= t('.hint')
 
   .gh-teacher-picker
     - if pool.addable?
       %label.gh-search-input.gh-search--full-width
         %i.fa-solid.fa-magnifying-glass{ 'aria-hidden': 'true' }
-        %input{ type: 'search', placeholder: 'Imię, nazwisko albo e-mail',
-                'aria-label': 'Szukaj nauczyciela', autocomplete: 'off', autofocus: true,
+        %input{ type: 'search', placeholder: t('.placeholder'),
+                'aria-label': t('.search'), autocomplete: 'off', autofocus: true,
                 data: { teacher_picker_target: 'input',
                         action: 'input->teacher-picker#filter keydown.enter->teacher-picker#noSubmit', } }
 
@@ -39,26 +36,23 @@
                 %small= teacher_candidate_subtitle(candidate, cross_university: pool.cross_university?)
 
               - if candidate.in_group?
-                %span.gh-badge-picker-status Już w grupie
+                %span.gh-badge-picker-status= t('.in_group')
               - else
                 %button.gh-btn.gh-btn--secondary.gh-btn--small{ type: 'submit',
                                                        name: 'story_group_teacher[user_id]',
                                                        value: candidate.person.id,
-                                                       'aria-label': "Dodaj #{candidate.name}" }
+                                                       'aria-label': t('.add_label', name: candidate.name) }
                   %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-                  Dodaj
+                  = t('shared.actions.add')
 
-        %p.gh-small{ hidden: true, data: { teacher_picker_target: 'overflow' } }
-          Nie widzisz tej osoby? Wpisz więcej liter albo e-mail.
+        %p.gh-small{ hidden: true, data: { teacher_picker_target: 'overflow' } }= t('.overflow_hint')
 
         %p.gh-explainer-note{ hidden: true, data: { teacher_picker_target: 'empty' } }
-          Brak wyników dla
+          = t('.no_results')
           %span{ data: { teacher_picker_target: 'emptyQuery' } }
-          Sprawdź pisownię albo wpisz e-mail.
+          = t('.no_results_hint')
     - else
-      %p.gh-explainer-note
-        Nie ma kogo dodać: w Twojej uczelni nie ma jeszcze innych kont
-        nauczycieli.
+      %p.gh-explainer-note= t('.nobody')
 
   - if error
     %p.gh-field-error{ role: 'alert' }
@@ -67,6 +61,6 @@
 
   .gh-dialog-button-row
     - if @in_modal
-      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } } Zamknij
+      %button.gh-btn.gh-btn--secondary{ type: 'button', data: { action: 'dialog#close' } }= t('shared.actions.close')
     - else
-      = link_to 'Zamknij', story_group_teachers_path(@story_group), class: 'gh-btn gh-btn--secondary'
+      = link_to t('shared.actions.close'), story_group_teachers_path(@story_group), class: 'gh-btn gh-btn--secondary'
diff --git a/app/views/teachers/_row.html.haml b/app/views/teachers/_row.html.haml
index f2685b60..c2126b64 100644
--- a/app/views/teachers/_row.html.haml
+++ b/app/views/teachers/_row.html.haml
@@ -11,20 +11,20 @@
 
   %span.gh-teacher-role
     - if row.owner?
-      Właściciel
-      %small Utworzył grupę
+      = t('.owner')
+      %small= t('.created_group')
     - else
-      Nauczyciel wspomagający
+      = t('.assistant')
 
   %span
-    %span.gh-mobile-field-label Dodano
+    %span.gh-mobile-field-label= t('.added')
     %span.gh-small= teacher_added_on(row.added_at)
 
   %span.gh-teacher-row-actions
     - if manage && row.removable?
       = link_to confirm_destroy_story_group_teacher_path(@story_group, row.membership),
         class: 'gh-btn gh-btn--secondary gh-btn--small',
-        'aria-label': "Usuń z grupy: #{name}",
+        'aria-label': t('.remove_label', name: name),
         data: { turbo_frame: 'modal' } do
         %i.fa-solid.fa-trash{ 'aria-hidden': 'true' }
-        Usuń
+        = t('shared.actions.remove')
diff --git a/app/views/teachers/confirm_destroy.html.haml b/app/views/teachers/confirm_destroy.html.haml
index 3d275f04..45db430c 100644
--- a/app/views/teachers/confirm_destroy.html.haml
+++ b/app/views/teachers/confirm_destroy.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, "Usunąć #{@teacher.full_name} z grupy?"
+- content_for :title, t('.page_title', name: @teacher.full_name)
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/app/views/teachers/index.html.haml b/app/views/teachers/index.html.haml
index 67ed014e..49b90966 100644
--- a/app/views/teachers/index.html.haml
+++ b/app/views/teachers/index.html.haml
@@ -1,23 +1,23 @@
-- content_for :title, 'Nauczyciele'
+- content_for :title, t('.title')
 
 - manage = policy(@story_group).manage_teachers?
 
 %section.gh-panel.gh-page-header
   .gh-page-header-text
-    %h1.gh-h1 Nauczyciele
+    %h1.gh-h1= t('.title')
     %p.gh-lead= teacher_list_lead(manage: manage)
 
   - if manage
     = link_to new_story_group_teacher_path(@story_group), class: 'gh-btn',
       data: { turbo_frame: 'modal' } do
       %i.fa-solid.fa-plus{ 'aria-hidden': 'true' }
-      Dodaj nauczyciela
+      = t('.add')
 
 %section.gh-panel.gh-teachers-panel
   .gh-teacher-row.gh-teacher-row--header{ 'aria-hidden': 'true' }
-    %span Nauczyciel
-    %span Rola
-    %span Dodano
+    %span= t('.teacher')
+    %span= t('.role')
+    %span= t('.added')
     %span
 
   = render partial: 'row', collection: @list.rows, as: :row, locals: { manage: manage }
diff --git a/app/views/teachers/new.html.haml b/app/views/teachers/new.html.haml
index 705e1d18..89f43c23 100644
--- a/app/views/teachers/new.html.haml
+++ b/app/views/teachers/new.html.haml
@@ -1,4 +1,4 @@
-- content_for :title, 'Dodaj nauczyciela'
+- content_for :title, t('.page_title')
 
 - if @in_modal
   = turbo_frame_tag 'modal' do
diff --git a/config/application.rb b/config/application.rb
index 37779237..82c53ca5 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -30,5 +30,9 @@ class Application < Rails::Application
     config.generators.system_tests = nil
 
     config.action_controller.include_all_helpers = false
+
+    config.i18n.available_locales = %i[pl en]
+    config.i18n.default_locale = :pl
+    config.i18n.load_path += Dir[Rails.root.join('config/locales/**/*.yml')]
   end
 end
diff --git a/config/environments/development.rb b/config/environments/development.rb
index ed7024c8..d0e02491 100644
--- a/config/environments/development.rb
+++ b/config/environments/development.rb
@@ -71,7 +71,7 @@
   config.assets.quiet = true
 
   # Raises error for missing translations.
-  # config.i18n.raise_on_missing_translations = true
+  config.i18n.raise_on_missing_translations = true
 
   # Annotate rendered view with file names.
   config.action_view.annotate_rendered_view_with_filenames = true
diff --git a/config/environments/test.rb b/config/environments/test.rb
index 37fc1f7b..7effe50a 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -45,7 +45,7 @@
   config.active_support.deprecation = :stderr
 
   # Raises error for missing translations.
-  # config.i18n.raise_on_missing_translations = true
+  config.i18n.raise_on_missing_translations = true
 
   # Annotate rendered view with file names.
   # config.action_view.annotate_rendered_view_with_filenames = true
diff --git a/config/locales/views/activity_group_templates.en.yml b/config/locales/views/activity_group_templates.en.yml
new file mode 100644
index 00000000..cf0aa194
--- /dev/null
+++ b/config/locales/views/activity_group_templates.en.yml
@@ -0,0 +1,40 @@
+en:
+  activity_group_templates:
+    flash:
+      created: "Created the template “%{name}”."
+      updated: "Saved the template. New sheets will get these categories."
+      destroyed: "Deleted the template “%{name}”. Sheets created from it stay."
+    # The first category a new template starts with.
+    default_category: "Attendance"
+
+    new:
+      page_title: "New sheet template"
+
+    edit:
+      page_title: "Edit template %{name}"
+
+    confirm_destroy:
+      page_title: "Delete template %{name}"
+      title: "Delete the template “%{name}”?"
+      body: "The template will disappear from the list, and sheets created from it stay."
+      sheets:
+        one: "%{count} sheet stays unchanged: %{names}"
+        other: "%{count} sheets stay unchanged: %{names}"
+      remove: "Delete template"
+
+  activerecord:
+    errors:
+      models:
+        activity_group_template:
+          attributes:
+            base_name:
+              blank: "Enter the template name."
+            base:
+              no_category: "Add at least one visible category."
+        # RewardCategory — a category of a template.
+        activity_group_template_category:
+          attributes:
+            didactic_description:
+              blank: "Say what the reward is for."
+            reward:
+              too_low: "The reward must be at least 1."
diff --git a/config/locales/views/activity_group_templates.pl.yml b/config/locales/views/activity_group_templates.pl.yml
new file mode 100644
index 00000000..3c40ea66
--- /dev/null
+++ b/config/locales/views/activity_group_templates.pl.yml
@@ -0,0 +1,42 @@
+pl:
+  activity_group_templates:
+    flash:
+      created: "Utworzono szablon „%{name}”."
+      updated: "Zapisano szablon. Nowe arkusze dostaną te kategorie."
+      destroyed: "Usunięto szablon „%{name}”. Utworzone z niego arkusze zostają."
+    # The first category a new template starts with.
+    default_category: "Obecność"
+
+    new:
+      page_title: "Nowy szablon arkusza"
+
+    edit:
+      page_title: "Edytuj szablon %{name}"
+
+    confirm_destroy:
+      page_title: "Usuń szablon %{name}"
+      title: "Usunąć szablon „%{name}”?"
+      body: "Szablon zniknie z listy, a utworzone z niego arkusze zostają."
+      sheets:
+        one: "%{count} arkusz zostaje bez zmian: %{names}"
+        few: "%{count} arkusze zostają bez zmian: %{names}"
+        many: "%{count} arkuszy zostaje bez zmian: %{names}"
+        other: "%{count} arkusza zostaje bez zmian: %{names}"
+      remove: "Usuń szablon"
+
+  activerecord:
+    errors:
+      models:
+        activity_group_template:
+          attributes:
+            base_name:
+              blank: "Podaj nazwę szablonu."
+            base:
+              no_category: "Dodaj co najmniej jedną widoczną kategorię."
+        # RewardCategory — a category of a template.
+        activity_group_template_category:
+          attributes:
+            didactic_description:
+              blank: "Podaj, za co jest nagroda."
+            reward:
+              too_low: "Nagroda musi wynosić co najmniej 1."
diff --git a/config/locales/views/activity_groups.en.yml b/config/locales/views/activity_groups.en.yml
new file mode 100644
index 00000000..26302086
--- /dev/null
+++ b/config/locales/views/activity_groups.en.yml
@@ -0,0 +1,84 @@
+en:
+  activity_groups:
+    flash:
+      created_one: "Created: %{name}."
+      created_many: "Created: %{first} – %{last}."
+      updated: "Saved the settings of the sheet %{name}."
+      destroyed: "Deleted the sheet %{name}. Awarded rewards stay in the students' history."
+
+    index:
+      title: "Grade sheets"
+      lead: "Sheets grouped by template. The newest are at the top."
+      new_template: "New template"
+      empty_title: "You don't have any templates yet"
+      empty_body: "A template is a set of categories you reward students for. From one template you then create sheets — one per class."
+
+    template_panel:
+      meta:
+        one: "Template: %{count} category, up to %{max} %{currency} per student per sheet."
+        other: "Template: %{count} categories, up to %{max} %{currency} per student per sheet."
+      edit: "Edit template"
+      create_sheet: "Create a sheet"
+      no_sheets: "No sheets have been created from this template yet."
+
+    sheet_row:
+      modified: "Columns changed"
+      awarded:
+        one: "Awarded %{count} reward"
+        other: "Awarded %{count} rewards"
+      nothing: "Nothing awarded yet"
+      grade: "Grade"
+      settings: "Sheet settings"
+      settings_label: "Settings: %{name}"
+
+    new:
+      page_title: "New sheet from the template %{name}"
+
+    new_form:
+      title: "New sheet from the template %{name}"
+      columns:
+        one: "Each sheet gets %{count} category from the template."
+        other: "Each sheet gets %{count} categories from the template."
+      columns_note: "You'll change the columns later in the sheet settings."
+      how_many: "How many sheets"
+      one: "One sheet"
+      many: "Several at once"
+      name_hint: "You can add a date, e.g. %{example} (14.10)."
+      count: "How many sheets to create"
+      names: "Names"
+      # sheet_create_controller.ts
+      js:
+        create_one: "Create sheet"
+        create_many:
+          one: "Create %{count} sheet"
+          other: "Create %{count} sheets"
+
+    edit:
+      page_title: "Sheet settings %{name}"
+
+    confirm_destroy:
+      page_title: "Delete sheet %{name}"
+      title: "Delete the sheet “%{name}”?"
+      body: "The sheet will disappear from the list, and awarded rewards stay with the students and in their history."
+      awarded:
+        one: "%{count} reward was awarded from it."
+        other: "%{count} rewards were awarded from it."
+      nothing_undone: "Deleting the sheet doesn't undo anything."
+      remove: "Delete sheet"
+
+  activerecord:
+    errors:
+      models:
+        activity_group:
+          attributes:
+            name:
+              blank: "Enter the sheet name."
+            base:
+              no_visible_category: "Add at least one visible category."
+        # RewardCategory — a column of a sheet.
+        activity_group_category:
+          attributes:
+            didactic_description:
+              blank: "Say what the reward is for."
+            reward:
+              too_low: "The reward must be at least 1."
diff --git a/config/locales/views/activity_groups.pl.yml b/config/locales/views/activity_groups.pl.yml
new file mode 100644
index 00000000..ea529902
--- /dev/null
+++ b/config/locales/views/activity_groups.pl.yml
@@ -0,0 +1,94 @@
+pl:
+  activity_groups:
+    flash:
+      created_one: "Utworzono: %{name}."
+      created_many: "Utworzono: %{first} – %{last}."
+      updated: "Zapisano ustawienia arkusza %{name}."
+      destroyed: "Usunięto arkusz %{name}. Przyznane nagrody zostają w historii studentów."
+
+    index:
+      title: "Arkusze ocen"
+      lead: "Arkusze pogrupowane według szablonów. Najnowsze są na górze."
+      new_template: "Nowy szablon"
+      empty_title: "Nie masz jeszcze żadnego szablonu"
+      empty_body: "Szablon to zestaw kategorii, za które nagradzasz studentów. Z jednego szablonu tworzysz potem kolejne arkusze — po jednym na zajęcia."
+
+    template_panel:
+      meta:
+        one: "Szablon: %{count} kategoria, do %{max} %{currency} na studenta za arkusz."
+        few: "Szablon: %{count} kategorie, do %{max} %{currency} na studenta za arkusz."
+        many: "Szablon: %{count} kategorii, do %{max} %{currency} na studenta za arkusz."
+        other: "Szablon: %{count} kategorii, do %{max} %{currency} na studenta za arkusz."
+      edit: "Edytuj szablon"
+      create_sheet: "Utwórz arkusz"
+      no_sheets: "Z tego szablonu nie utworzono jeszcze arkuszy."
+
+    sheet_row:
+      modified: "Zmienione kolumny"
+      awarded:
+        one: "Przyznano %{count} nagrodę"
+        few: "Przyznano %{count} nagrody"
+        many: "Przyznano %{count} nagród"
+        other: "Przyznano %{count} nagrody"
+      nothing: "Jeszcze nic nie przyznano"
+      grade: "Oceń"
+      settings: "Ustawienia arkusza"
+      settings_label: "Ustawienia: %{name}"
+
+    new:
+      page_title: "Nowy arkusz z szablonu %{name}"
+
+    new_form:
+      title: "Nowy arkusz z szablonu %{name}"
+      columns:
+        one: "Każdy arkusz dostanie %{count} kategorię z szablonu."
+        few: "Każdy arkusz dostanie %{count} kategorie z szablonu."
+        many: "Każdy arkusz dostanie %{count} kategorii z szablonu."
+        other: "Każdy arkusz dostanie %{count} kategorii z szablonu."
+      columns_note: "Kolumny zmienisz później w ustawieniach arkusza."
+      how_many: "Ile arkuszy"
+      one: "Jeden arkusz"
+      many: "Kilka naraz"
+      name_hint: "Możesz dopisać datę, np. %{example} (14.10)."
+      count: "Ile arkuszy utworzyć"
+      names: "Nazwy"
+      # sheet_create_controller.ts
+      js:
+        create_one: "Utwórz arkusz"
+        create_many:
+          one: "Utwórz %{count} arkusz"
+          few: "Utwórz %{count} arkusze"
+          many: "Utwórz %{count} arkuszy"
+          other: "Utwórz %{count} arkusza"
+
+    edit:
+      page_title: "Ustawienia arkusza %{name}"
+
+    confirm_destroy:
+      page_title: "Usuń arkusz %{name}"
+      title: "Usunąć arkusz „%{name}”?"
+      body: "Arkusz zniknie z listy, a przyznane nagrody zostają u studentów i w ich historii."
+      awarded:
+        one: "Przyznano z niego %{count} nagrodę."
+        few: "Przyznano z niego %{count} nagrody."
+        many: "Przyznano z niego %{count} nagród."
+        other: "Przyznano z niego %{count} nagrody."
+      nothing_undone: "Usunięcie arkusza niczego nie cofa."
+      remove: "Usuń arkusz"
+
+  activerecord:
+    errors:
+      models:
+        activity_group:
+          attributes:
+            name:
+              blank: "Podaj nazwę arkusza."
+            base:
+              no_visible_category: "Dodaj co najmniej jedną widoczną kategorię."
+        # RewardCategory — a column of a sheet.
+        activity_group_category:
+          attributes:
+            didactic_description:
+              blank: "Podaj, za co jest nagroda."
+            reward:
+              too_low: "Nagroda musi wynosić co najmniej 1."
diff --git a/config/locales/views/application.en.yml b/config/locales/views/application.en.yml
new file mode 100644
index 00000000..7ba07fc0
--- /dev/null
+++ b/config/locales/views/application.en.yml
@@ -0,0 +1,79 @@
+en:
+  # ApplicationHelper and ApplicationController concerns — wording shared by many screens.
+  application:
+    flash:
+      log_in_first: "Log in to continue."
+      already_signed_in: "You're already logged in."
+      not_found: "Not found."
+    helpers:
+      today: "today %{time}"
+      yesterday: "yesterday %{time}"
+      minutes:
+        one: "%{count} minute"
+        other: "%{count} minutes"
+      feed:
+        purchase: "Purchase: %{name}"
+        purchase_fallback: "Purchase"
+        reward_fallback: "Activity reward"
+        adjustment: "Currency adjustment"
+      transaction:
+        purchase: "%{student} bought %{item} for %{amount} %{currency}"
+        item_fallback: "an item"
+        reward: "%{student} earned a reward for: %{category}"
+        category_fallback: "activity"
+        adjustment: "%{adjuster} adjusted %{student}'s currency (%{amount})"
+        adjuster_fallback: "the teacher"
+    # PresetSet.label_for — names of the ready-made images, read out by screen readers.
+    presets:
+      glyphs:
+        bolt: "Lightning bolt"
+        carrot: "Carrot"
+        carrotStar: "Carrot with a star"
+        chat: "Conversation"
+        chev1: "Chevron"
+        chev2: "Double chevron"
+        clock: "Clock"
+        compass: "Compass"
+        crew: "Crew"
+        crown: "Crown"
+        flask: "Flask"
+        heartPlus: "Heart with a plus"
+        hourglass: "Hourglass"
+        note: "Envelope"
+        paperCheck: "Sheet with a tick"
+        papers3: "Three sheets"
+        papers3shield: "Three sheets with a shield"
+        percent: "Percent"
+        rabbit: "Rabbit"
+        retake: "Sheet with an arrow"
+        rocket: "Rocket"
+        shield: "Shield"
+        starPlus: "Star with a sparkle"
+        starTrail: "Shooting star"
+        wrench: "Wrench"
+      art:
+        brackets: "Code"
+        castle: "Castle"
+        flow: "Algorithm"
+        tables: "Tables"
+        waves: "Sea"
+      currency:
+        bit: "Bit"
+        carrot: "Carrot"
+        coin: "Coin"
+        gem: "Gem"
+        pearl: "Pearl"
+
+  # Iconable — shared by every model with a picture.
+  activerecord:
+    errors:
+      messages:
+        unknown_art: "Unknown image."
+        unknown_icon: "Unknown icon."
+        art_type: "The image must be a GIF, JPG or PNG file."
+        art_missing: "Choose a ready-made image or upload your own."
+
+  time:
+    formats:
+      gh_time: "%H:%M"
+      gh_day_time: "%b %-d, %H:%M"
diff --git a/config/locales/views/application.pl.yml b/config/locales/views/application.pl.yml
new file mode 100644
index 00000000..52763027
--- /dev/null
+++ b/config/locales/views/application.pl.yml
@@ -0,0 +1,81 @@
+pl:
+  # ApplicationHelper and ApplicationController concerns — wording shared by many screens.
+  application:
+    flash:
+      log_in_first: "Zaloguj się, aby kontynuować."
+      already_signed_in: "Jesteś już zalogowany."
+      not_found: "Nie znaleziono."
+    helpers:
+      today: "dziś %{time}"
+      yesterday: "wczoraj %{time}"
+      minutes:
+        one: "%{count} minuta"
+        few: "%{count} minuty"
+        many: "%{count} minut"
+        other: "%{count} minuty"
+      feed:
+        purchase: "Zakup: %{name}"
+        purchase_fallback: "Zakup"
+        reward_fallback: "Nagroda za aktywność"
+        adjustment: "Korekta waluty"
+      transaction:
+        purchase: "%{student} zakupił %{item} za %{amount} %{currency}"
+        item_fallback: "przedmiot"
+        reward: "%{student} zdobył nagrodę za: %{category}"
+        category_fallback: "aktywność"
+        adjustment: "%{adjuster} skorygował walutę %{student} (%{amount})"
+        adjuster_fallback: "nauczyciel"
+    # PresetSet.label_for — names of the ready-made images, read out by screen readers.
+    presets:
+      glyphs:
+        bolt: "Błyskawica"
+        carrot: "Marchewka"
+        carrotStar: "Marchewka z gwiazdą"
+        chat: "Rozmowa"
+        chev1: "Belka"
+        chev2: "Podwójna belka"
+        clock: "Zegar"
+        compass: "Kompas"
+        crew: "Załoga"
+        crown: "Korona"
+        flask: "Kolba"
+        heartPlus: "Serce z plusem"
+        hourglass: "Klepsydra"
+        note: "Koperta"
+        paperCheck: "Kartka z ptaszkiem"
+        papers3: "Trzy kartki"
+        papers3shield: "Trzy kartki z tarczą"
+        percent: "Procent"
+        rabbit: "Królik"
+        retake: "Kartka ze strzałką"
+        rocket: "Rakieta"
+        shield: "Tarcza"
+        starPlus: "Gwiazda z gwiazdką"
+        starTrail: "Gwiazda ze smugą"
+        wrench: "Klucz"
+      art:
+        brackets: "Kod"
+        castle: "Zamek"
+        flow: "Algorytm"
+        tables: "Tabele"
+        waves: "Morze"
+      currency:
+        bit: "Bit"
+        carrot: "Marchewka"
+        coin: "Moneta"
+        gem: "Klejnot"
+        pearl: "Perła"
+
+  # Iconable — shared by every model with a picture.
+  activerecord:
+    errors:
+      messages:
+        unknown_art: "Nieznana grafika."
+        unknown_icon: "Nieznana ikona."
+        art_type: "Grafika musi być plikiem GIF, JPG lub PNG."
+        art_missing: "Wybierz gotową grafikę albo wgraj własną."
+
+  time:
+    formats:
+      gh_time: "%H:%M"
+      gh_day_time: "%d.%m, %H:%M"
diff --git a/config/locales/views/auth.en.yml b/config/locales/views/auth.en.yml
new file mode 100644
index 00000000..24b201e0
--- /dev/null
+++ b/config/locales/views/auth.en.yml
@@ -0,0 +1,27 @@
+en:
+  # Auth::PasswordlessController, Auth::UsosController and Auth::SignIn.
+  auth:
+    flash:
+      signed_in: "Logged in successfully."
+      invalid_token: "Invalid token"
+      resent: "We've sent a new link. The previous one no longer works."
+      invalid_provider: "Invalid login provider."
+      invalid_auth: "Invalid authorization attempt."
+
+    passwordless:
+      new:
+        title: "Log in with e-mail"
+        back: "Other ways to log in"
+        lead: "We'll send you a login link. No password needed."
+        email: "E-mail address"
+        placeholder: "john.smith@example.com"
+        send: "Send link"
+      inbox:
+        title: "Check your inbox"
+        sent_to: "We've sent a link to"
+        valid_for: "The link works for %{minutes}."
+        spam: "If you can't see it, check your Spam folder."
+        # %{time} is filled in by countdown_controller.ts.
+        waiting: "Resend in %{time}"
+        resend: "Resend the link"
+        change_email: "Change e-mail address"
diff --git a/config/locales/views/auth.pl.yml b/config/locales/views/auth.pl.yml
new file mode 100644
index 00000000..9bba17d8
--- /dev/null
+++ b/config/locales/views/auth.pl.yml
@@ -0,0 +1,27 @@
+pl:
+  # Auth::PasswordlessController, Auth::UsosController and Auth::SignIn.
+  auth:
+    flash:
+      signed_in: "Zalogowano pomyślnie."
+      invalid_token: "Nieprawidłowy token"
+      resent: "Wysłaliśmy nowy link. Poprzedni już nie działa."
+      invalid_provider: "Nieprawidłowy dostawca logowania."
+      invalid_auth: "Nieprawidłowa próba autoryzacji."
+
+    passwordless:
+      new:
+        title: "Logowanie e-mailem"
+        back: "Inne sposoby logowania"
+        lead: "Wyślemy Ci link do logowania. Hasło nie jest potrzebne."
+        email: "Adres e-mail"
+        placeholder: "jan.nowak@example.com"
+        send: "Wyślij link"
+      inbox:
+        title: "Sprawdź skrzynkę"
+        sent_to: "Wysłaliśmy link na adres"
+        valid_for: "Link działa przez %{minutes}."
+        spam: "Jeśli go nie widzisz, zajrzyj do folderu Spam."
+        # %{time} is filled in by countdown_controller.ts.
+        waiting: "Wyślij ponownie za %{time}"
+        resend: "Wyślij link ponownie"
+        change_email: "Zmień adres e-mail"
diff --git a/config/locales/views/badges.en.yml b/config/locales/views/badges.en.yml
new file mode 100644
index 00000000..31ebca9b
--- /dev/null
+++ b/config/locales/views/badges.en.yml
@@ -0,0 +1,110 @@
+en:
+  badges:
+    flash:
+      created: "Added the “%{name}” badge."
+      updated: "Saved the “%{name}” badge."
+      destroyed: "Deleted the “%{name}” badge. Students who have it keep it in their history."
+
+    helpers:
+      nobody_holds: "Nobody has it yet"
+      holders:
+        one: "%{count} student has it"
+        other: "%{count} students have it"
+      discount: "−%{discount}% in the shop"
+      rule_placeholder: "How to earn it…"
+      name_placeholder: "Badge name"
+
+    index:
+      title: "Badges"
+
+    new:
+      page_title: "New badge"
+
+    edit:
+      page_title: "Edit badge - %{name}"
+
+    teacher_grid:
+      title: "Badges"
+      lead:
+        one: "%{count} badge. You award them by hand, from this list or from the student list."
+        other: "%{count} badges. You award them by hand, from this list or from the student list."
+      new: "New badge"
+      award: "Award"
+      edit_label: "Edit badge %{name}"
+      empty_title: "There are no badges yet"
+      empty_body: "Add badges to reward what points don't show. You award them by hand, and each can give a discount in the shop."
+
+    student_deck:
+      title: "Badges"
+      lead: "You have %{earned} of %{total}. Badges are awarded by the teacher. The back of each one you don't have yet tells you how to earn it."
+      empty_title: "This group has no badges yet"
+      empty_body: "The teacher hasn't added any. Once they do, you'll see here what it takes to earn them."
+
+    flip_card:
+      label: "Badge %{name}"
+      label_unearned: "Badge %{name}, not earned yet"
+
+    front:
+      removed: "Removed from the list"
+      flip_label: "Show how to earn the %{name} badge"
+      flip: "How to earn it"
+
+    back:
+      how: "How to earn it"
+      flip_label: "Show the %{name} badge"
+      flip: "Show badge"
+
+    preview:
+      summary: "Card preview"
+      students_view: "This is what students will see"
+      side: "Card side"
+      earned: "Earned"
+      unearned: "Not earned yet"
+      picker: "In the award dialog"
+
+    form:
+      breadcrumb: "Badges"
+      new_title: "New badge"
+      edit_title: "Edit badge"
+      lead: "The preview shows both sides of the card: earned and not earned yet."
+      holders:
+        one: "%{count} student has this badge."
+        other: "%{count} students have this badge."
+      holders_note: "A discount change applies to their next purchases right away."
+      card: "Badge card"
+      card_hint: "This is how the badge looks in the student's deck and in the award dialog."
+      name_placeholder: "e.g. Flawless Flight"
+      rule: "How to earn it"
+      rule_placeholder: "e.g. At least 3 quizzes in a row without mistakes"
+      rule_hint: "Students see this on the back of a badge they don't have yet. Be specific."
+      story: "Story description"
+      story_placeholder: "e.g. A flight without a single scratch"
+      discount_section: "Shop discount"
+      discount_hint: "Only applies to items that count it. You set that in the item form."
+      discount: "Shop discount"
+      used_by: "Counted by"
+      unused: "No item counts it yet."
+      removal_hint: "The badge will disappear from the list and from the award dialog. Students who have it keep it in their history."
+      remove: "Delete badge"
+      create: "Add badge"
+
+    confirm_destroy:
+      page_title: "Delete badge %{name}"
+      title: "Delete the “%{name}” badge?"
+      body: "Students who have this badge keep it in their history, but nobody new will get it."
+      unlocking:
+        one: "The item %{items} is unlocked by this badge, and after deleting it only those who already have the badge can buy it."
+        other: "The items %{items} are unlocked by this badge, and after deleting it only those who already have the badge can buy them."
+      remove: "Delete badge"
+
+  activerecord:
+    errors:
+      models:
+        badge:
+          attributes:
+            name:
+              blank: "Enter the badge name."
+            didactic_description:
+              blank: "Describe how to earn this badge."
+            discount:
+              out_of_range: "The discount must be between 0 and 100%."
diff --git a/config/locales/views/badges.pl.yml b/config/locales/views/badges.pl.yml
new file mode 100644
index 00000000..5c56cae9
--- /dev/null
+++ b/config/locales/views/badges.pl.yml
@@ -0,0 +1,116 @@
+pl:
+  badges:
+    flash:
+      created: "Dodano odznakę „%{name}”."
+      updated: "Zapisano odznakę „%{name}”."
+      destroyed: "Usunięto odznakę „%{name}”. Studenci, którzy ją mają, zachowują ją w historii."
+
+    helpers:
+      nobody_holds: "Nikt jej jeszcze nie ma"
+      holders:
+        one: "Ma ją %{count} student"
+        few: "Ma ją %{count} studentów"
+        many: "Ma ją %{count} studentów"
+        other: "Ma ją %{count} studenta"
+      discount: "−%{discount}% w sklepie"
+      rule_placeholder: "Jak zdobyć…"
+      name_placeholder: "Nazwa odznaki"
+
+    index:
+      title: "Odznaki"
+
+    new:
+      page_title: "Nowa odznaka"
+
+    edit:
+      page_title: "Edytuj odznakę - %{name}"
+
+    teacher_grid:
+      title: "Odznaki"
+      lead:
+        one: "%{count} odznaka. Przyznajesz je ręcznie, z tej listy albo z listy studentów."
+        few: "%{count} odznaki. Przyznajesz je ręcznie, z tej listy albo z listy studentów."
+        many: "%{count} odznak. Przyznajesz je ręcznie, z tej listy albo z listy studentów."
+        other: "%{count} odznaki. Przyznajesz je ręcznie, z tej listy albo z listy studentów."
+      new: "Nowa odznaka"
+      award: "Przyznaj"
+      edit_label: "Edytuj odznakę %{name}"
+      empty_title: "Nie ma jeszcze żadnych odznak"
+      empty_body: "Dodaj odznaki, żeby mieć czym nagradzać to, czego nie widać w punktach. Przyznajesz je ręcznie, a każda może dawać zniżkę w sklepie."
+
+    student_deck:
+      title: "Odznaki"
+      lead: "Masz %{earned} z %{total}. Odznaki przyznaje prowadzący. Na odwrocie każdej niezdobytej znajdziesz, jak ją zdobyć."
+      empty_title: "W tej grupie nie ma jeszcze odznak"
+      empty_body: "Prowadzący ich nie dodał. Kiedy się pojawią, zobaczysz tu, co trzeba zrobić, żeby je zdobyć."
+
+    flip_card:
+      label: "Odznaka %{name}"
+      label_unearned: "Odznaka %{name}, jeszcze niezdobyta"
+
+    front:
+      removed: "Usunięta z listy"
+      flip_label: "Pokaż, jak zdobyć odznakę %{name}"
+      flip: "Jak zdobyć"
+
+    back:
+      how: "Jak zdobyć"
+      flip_label: "Pokaż odznakę %{name}"
+      flip: "Pokaż odznakę"
+
+    preview:
+      summary: "Podgląd karty"
+      students_view: "Tak zobaczą to studenci"
+      side: "Strona karty"
+      earned: "Zdobyta"
+      unearned: "Jeszcze niezdobyta"
+      picker: "W oknie przyznawania"
+
+    form:
+      breadcrumb: "Odznaki"
+      new_title: "Nowa odznaka"
+      edit_title: "Edytuj odznakę"
+      lead: "Podgląd obok pokazuje obie strony karty: zdobytą i jeszcze niezdobytą."
+      holders:
+        one: "%{count} student ma tę odznakę."
+        few: "%{count} studentów ma tę odznakę."
+        many: "%{count} studentów ma tę odznakę."
+        other: "%{count} studenta ma tę odznakę."
+      holders_note: "Zmiana zniżki od razu obejmie ich kolejne zakupy."
+      card: "Karta odznaki"
+      card_hint: "Tak odznaka wygląda w talii studenta i w oknie przyznawania."
+      name_placeholder: "np. Perfekcyjny Lot"
+      rule: "Jak zdobyć"
+      rule_placeholder: "np. Co najmniej 3 wejściówki z rzędu bez błędów"
+      rule_hint: "Studenci widzą to na odwrocie odznaki, której jeszcze nie mają. Pisz konkretnie."
+      story: "Opis fabularny"
+      story_placeholder: "np. Lot bez najmniejszej rysy"
+      discount_section: "Zniżka w sklepie"
+      discount_hint: "Działa tylko na przedmioty, które ją uwzględniają. Ustawiasz to w formularzu przedmiotu."
+      discount: "Zniżka w sklepie"
+      used_by: "Uwzględniają ją"
+      unused: "Na razie żaden przedmiot jej nie uwzględnia."
+      removal_hint: "Odznaka zniknie z listy i z okna przyznawania. Studenci, którzy ją mają, zachowają ją w historii."
+      remove: "Usuń odznakę"
+      create: "Dodaj odznakę"
+
+    confirm_destroy:
+      page_title: "Usuń odznakę %{name}"
+      title: "Usunąć odznakę „%{name}”?"
+      body: "Studenci, którzy mają tę odznakę, zachowają ją w historii, ale nikt nowy jej nie dostanie."
+      unlocking:
+        one: "Przedmiot %{items} odblokowuje się tą odznaką i po usunięciu kupi go tylko ci, którzy już ją mają."
+        other: "Przedmioty %{items} odblokowują się tą odznaką i po usunięciu kupią je tylko ci, którzy już ją mają."
+      remove: "Usuń odznakę"
+
+  activerecord:
+    errors:
+      models:
+        badge:
+          attributes:
+            name:
+              blank: "Podaj nazwę odznaki."
+            didactic_description:
+              blank: "Napisz, jak zdobyć tę odznakę."
+            discount:
+              out_of_range: "Zniżka musi mieścić się między 0 a 100%."
diff --git a/config/locales/views/currency_adjustments.en.yml b/config/locales/views/currency_adjustments.en.yml
new file mode 100644
index 00000000..c14e9d1e
--- /dev/null
+++ b/config/locales/views/currency_adjustments.en.yml
@@ -0,0 +1,37 @@
+en:
+  currency_adjustments:
+    flash:
+      added: "Added %{value}. Balance: %{balance}."
+      taken: "Subtracted %{value}. Balance: %{balance}."
+
+    new:
+      page_title: "Adjust currency - %{name}"
+
+    form:
+      title: "Adjust currency"
+      lead: "%{name} now has %{balance} to spend."
+      kind_label: "Adjustment type"
+      take: "Subtract"
+      amount: "Amount"
+      balance: "To spend"
+      total: "Collected in total"
+      rank: "Rank"
+      unchanged: "unchanged"
+      total_unchanged: "%{total} (unchanged)"
+      blank: "Enter an amount"
+      over: "The student only has %{balance} to spend."
+      add_note: "Adding also raises the collected total, so it may raise the rank."
+      take_note: "Subtracting only lowers what the student has to spend. The collected total and the rank stay the same."
+      submit_add: "Add %{value}"
+      submit_take: "Subtract %{value}"
+
+  # CurrencyAdjustmentForm#validate (errors.add(:amount, :key)).
+  activemodel:
+    errors:
+      models:
+        currency_adjustment_form:
+          attributes:
+            amount:
+              missing: "Enter an amount."
+              not_positive: "Enter an amount greater than zero."
+              overdrawn: "The student only has %{balance} to spend."
diff --git a/config/locales/views/currency_adjustments.pl.yml b/config/locales/views/currency_adjustments.pl.yml
new file mode 100644
index 00000000..fe283b64
--- /dev/null
+++ b/config/locales/views/currency_adjustments.pl.yml
@@ -0,0 +1,37 @@
+pl:
+  currency_adjustments:
+    flash:
+      added: "Dodano %{value}. Saldo: %{balance}."
+      taken: "Odjęto %{value}. Saldo: %{balance}."
+
+    new:
+      page_title: "Koryguj walutę - %{name}"
+
+    form:
+      title: "Koryguj walutę"
+      lead: "%{name} ma teraz %{balance} do wydania."
+      kind_label: "Rodzaj korekty"
+      take: "Odejmij"
+      amount: "Ile"
+      balance: "Do wydania"
+      total: "Zebrane łącznie"
+      rank: "Ranga"
+      unchanged: "bez zmian"
+      total_unchanged: "%{total} (bez zmian)"
+      blank: "Podaj kwotę"
+      over: "Student ma tylko %{balance} do wydania."
+      add_note: "Dodanie podnosi też sumę zebranych, więc może podnieść rangę."
+      take_note: "Odjęcie zmniejsza tylko to, co student ma do wydania. Suma zebranych i ranga zostają bez zmian."
+      submit_add: "Dodaj %{value}"
+      submit_take: "Odejmij %{value}"
+
+  # CurrencyAdjustmentForm#validate (errors.add(:amount, :key)).
+  activemodel:
+    errors:
+      models:
+        currency_adjustment_form:
+          attributes:
+            amount:
+              missing: "Podaj kwotę."
+              not_positive: "Podaj kwotę większą od zera."
+              overdrawn: "Student ma tylko %{balance} do wydania."
diff --git a/config/locales/views/currency_transactions.en.yml b/config/locales/views/currency_transactions.en.yml
new file mode 100644
index 00000000..2d83c754
--- /dev/null
+++ b/config/locales/views/currency_transactions.en.yml
@@ -0,0 +1,38 @@
+en:
+  currency_transactions:
+    # CurrencyLedger::KINDS — the filter chips name a set of rows.
+    filters:
+      all: "All"
+      reward: "Rewards"
+      purchase: "Purchases"
+      adjustment: "Adjustments"
+    # LedgerEntry#label — the pill on a single row.
+    kinds:
+      reward: "Reward"
+      purchase: "Purchase"
+      adjustment: "Adjustment"
+    # CurrencyLedger#title_for, when the row has no name of its own.
+    entry_titles:
+      reward: "Reward"
+      adjustment: "Currency adjustment"
+
+    helpers:
+      balance_sentence_html: "You have %{balance} to spend and %{total} collected in total."
+      summary_sentence_html: "Balance: %{balance}, collected in total: %{total}."
+
+    ledger:
+      table_label: "Currency history"
+      columns:
+        amount: "Amount"
+        kind: "Type"
+        source: "For"
+        when: "When"
+        balance_after: "Balance after"
+      withdrawn: "Removed from the shop"
+
+    index:
+      title: "Currency history"
+      go_to_shop: "Go to the shop"
+      empty_kind: "You have no entries of this type yet."
+      empty_title: "Your first entries will show up after class"
+      empty_body: "The teacher awards currency for attendance, punctuality and activity. Everything you earn and spend will be recorded here."
diff --git a/config/locales/views/currency_transactions.pl.yml b/config/locales/views/currency_transactions.pl.yml
new file mode 100644
index 00000000..30c1a192
--- /dev/null
+++ b/config/locales/views/currency_transactions.pl.yml
@@ -0,0 +1,38 @@
+pl:
+  currency_transactions:
+    # CurrencyLedger::KINDS — the filter chips name a set of rows.
+    filters:
+      all: "Wszystkie"
+      reward: "Nagrody"
+      purchase: "Zakupy"
+      adjustment: "Korekty"
+    # LedgerEntry#label — the pill on a single row.
+    kinds:
+      reward: "Nagroda"
+      purchase: "Zakup"
+      adjustment: "Korekta"
+    # CurrencyLedger#title_for, when the row has no name of its own.
+    entry_titles:
+      reward: "Nagroda"
+      adjustment: "Korekta waluty"
+
+    helpers:
+      balance_sentence_html: "Masz %{balance} do wydania i %{total} zebrane łącznie."
+      summary_sentence_html: "Saldo: %{balance}, zebrane łącznie: %{total}."
+
+    ledger:
+      table_label: "Historia waluty"
+      columns:
+        amount: "Kwota"
+        kind: "Typ"
+        source: "Za co"
+        when: "Kiedy"
+        balance_after: "Saldo po"
+      withdrawn: "Usunięty z oferty"
+
+    index:
+      title: "Historia waluty"
+      go_to_shop: "Przejdź do sklepu"
+      empty_kind: "Nie masz jeszcze wpisów tego typu."
+      empty_title: "Pierwsze wpisy pojawią się po zajęciach"
+      empty_body: "Prowadzący przyznaje walutę za obecność, punktualność i aktywność. Wszystko, co zdobędziesz i wydasz, zapisze się tutaj."
diff --git a/config/locales/views/home.en.yml b/config/locales/views/home.en.yml
new file mode 100644
index 00000000..5de1c44b
--- /dev/null
+++ b/config/locales/views/home.en.yml
@@ -0,0 +1,159 @@
+en:
+  home:
+    index:
+      title: "Home"
+
+    # HomeHelper#home_greeting — the admin dashboards.
+    admin_greeting: "Good morning, %{name}"
+    admin_greeting_anonymous: "Good morning"
+
+    capacity_bar:
+      unlimited:
+        one: "%{count} account · no limit"
+        other: "%{count} accounts · no limit"
+      label: "Seats taken"
+
+    # Dashboard::GlobalAdmin and home/_global_admin_start.
+    global_admin_start:
+      tiles:
+        organizations: "Organizations"
+        accounts: "Accounts in organizations"
+        free: "Free seats"
+        pending: "Invitations not accepted"
+      stats_label: "Organizations summary"
+      no_organizations_lead: "There are no organizations yet. Create the first one so new accounts have somewhere to go."
+      attention_lead:
+        one: "%{count} organization — some of them need your attention."
+        other: "%{count} organizations — some of them need your attention."
+      fine_lead:
+        one: "%{count} organization. All of them have an administrator and free seats."
+        other: "%{count} organizations. All of them have an administrator and free seats."
+      create: "Create an organization"
+      organizations: "Organizations"
+      admins:
+        one: "%{count} administrator"
+        other: "%{count} administrators"
+      pending_admins:
+        one: "%{count} invitation pending"
+        other: "%{count} invitations pending"
+      all_organizations: "All organizations"
+      attention: "Needs attention"
+      no_admin: "No administrator"
+      add: "Add"
+      no_free_seats: "No free seats"
+      free_seats:
+        one: "%{count} seat left"
+        other: "%{count} seats left"
+      limit: "Limit"
+      fine_title: "Everything is fine"
+      fine_body: "Every organization has an administrator and free seats."
+      how_title: "How it works"
+      how_body: "Everyone who signs in through USOS lands in the organization %{usos}. It has no seat limit and can't be deleted. Accounts in the other organizations are added by their administrators."
+      empty_title: "Start with the first organization"
+      empty_lead: "Set an account limit and add an administrator — they'll invite everyone else."
+
+    # Dashboard::OrganizationAdmin and home/_organization_admin_start.
+    organization_admin_start:
+      tiles:
+        students: "Students"
+        teachers: "Teachers"
+        free: "Free seats"
+        no_limit: "No limit"
+        of_max: "of %{max}"
+        pending: "Pending invitations"
+      stats_label: "Organization summary"
+      no_organization: "Your administrator account isn't assigned to any organization. Contact the system administrator."
+      full_lead: "The organization has no free seats — new people won't be able to join until someone is removed or the limit is raised."
+      pending_lead:
+        one: "%{count} person hasn't accepted the invitation yet."
+        other: "%{count} people haven't accepted the invitation yet."
+      users: "Users"
+      add_user: "Add a user"
+      recent: "Recently added"
+      invited: "Invitation sent"
+      added: "Added %{when}"
+      all_users: "All users"
+      nobody: "Nobody is here yet. Add students and teachers or wait until they sign in through the university."
+      seats: "Seats"
+      unlimited_note: "This organization has no seat limit. Everyone who signs in through USOS lands here automatically."
+      limited_note: "The limit is set by the system administrator. Every account, the administrator's included, takes one seat."
+      pending_title: "Waiting for the invitation to be accepted"
+
+    # TeacherStartDashboard::DAYS
+    days:
+      today: "Today"
+      yesterday: "Yesterday"
+      earlier: "Earlier"
+
+    teacher_start:
+      greeting: "Good morning, %{name}"
+      recent_lead: "Since yesterday students have bought %{items} %{groups}."
+      recent_items:
+        one: "%{count} item"
+        other: "%{count} items"
+      recent_groups:
+        one: "in %{count} group"
+        other: "in %{count} groups"
+      quiet_lead: "Nobody has bought anything since yesterday. Look into your groups below."
+      no_groups_lead: "You don't lead any groups yet. Create your first one to get started."
+      purchases: "Recent purchases"
+      filter: "Show purchases from group"
+      all_groups: "All groups"
+      removed_item: "Item removed from the shop"
+      no_group_purchases: "There are no purchases in this group yet."
+      no_purchases: "Nobody has bought anything yet. Purchases will show up here on their own."
+      pending: "Waiting to be graded"
+      pending_left: "%{categories} left for %{students}."
+      pending_categories:
+        one: "%{count} category"
+        other: "%{count} categories"
+      pending_students:
+        one: "%{count} student"
+        other: "%{count} students"
+      grade: "Grade"
+      your_groups: "Your groups"
+      group_meta: "%{role}, %{students}"
+      students:
+        one: "%{count} student"
+        other: "%{count} students"
+      new_purchases:
+        one: "%{count} new purchase"
+        other: "%{count} new purchases"
+      no_groups: "You don't lead any groups yet."
+      create_group: "Create a group"
+
+    student_start:
+      greeting: "Hi, %{name}"
+      groups_lead:
+        one: "You're in %{count} group. Currency, ranks and badges are separate in each one."
+        other: "You're in %{count} groups. Currency, ranks and badges are separate in each one."
+      no_groups_lead: "You're not in any group yet. Ask your teacher for a code and join below."
+      fresh: "You're just starting out. You'll earn your first %{currency} in class."
+      to_spend: "To spend"
+      lives: "Lives"
+      rank: "Rank:"
+      no_rank: "none"
+      to_next: "%{total} of %{needed} to the %{rank} rank"
+      top: "%{total} collected. This is the highest rank."
+      progress_label: "Progress to the next rank in the group %{name}"
+      badges: "Badges"
+      badges_of: "of %{total}"
+      open_group: "Open the group"
+      shop: "Shop"
+      have_code: "Got a code from your teacher?"
+      code_hint: "The code has 6 characters. You can also scan the QR code with your phone's camera."
+      join: "Join a group"
+      feed: "Recently across all groups"
+      feed_meta: "%{group}, %{when}"
+
+  notifications:
+    panel:
+      title: "Notifications"
+      mark_all: "Mark all as read"
+      new: "New"
+      earlier: "Earlier"
+      empty: "No notifications."
+    notification:
+      purchase: "Purchase: %{name}"
+      meta: "%{group}, %{when}"
+      unread: "new"
diff --git a/config/locales/views/home.pl.yml b/config/locales/views/home.pl.yml
new file mode 100644
index 00000000..926c7a98
--- /dev/null
+++ b/config/locales/views/home.pl.yml
@@ -0,0 +1,187 @@
+pl:
+  home:
+    index:
+      title: "Start"
+
+    # HomeHelper#home_greeting — the admin dashboards.
+    admin_greeting: "Dzień dobry, %{name}"
+    admin_greeting_anonymous: "Dzień dobry"
+
+    capacity_bar:
+      unlimited:
+        one: "%{count} konto · bez limitu"
+        few: "%{count} konta · bez limitu"
+        many: "%{count} kont · bez limitu"
+        other: "%{count} konta · bez limitu"
+      label: "Zajęte miejsca"
+
+    # Dashboard::GlobalAdmin and home/_global_admin_start.
+    global_admin_start:
+      tiles:
+        organizations: "Organizacje"
+        accounts: "Konta w organizacjach"
+        free: "Wolne miejsca"
+        pending: "Niezaakceptowane zaproszenia"
+      stats_label: "Podsumowanie organizacji"
+      no_organizations_lead: "Nie ma jeszcze żadnej organizacji. Utwórz pierwszą, żeby nowe konta miały gdzie trafić."
+      attention_lead:
+        one: "%{count} organizacja — część z nich potrzebuje Twojej uwagi."
+        few: "%{count} organizacje — część z nich potrzebuje Twojej uwagi."
+        many: "%{count} organizacji — część z nich potrzebuje Twojej uwagi."
+        other: "%{count} organizacji — część z nich potrzebuje Twojej uwagi."
+      fine_lead:
+        one: "%{count} organizacja. Wszystkie mają administratora i wolne miejsca."
+        few: "%{count} organizacje. Wszystkie mają administratora i wolne miejsca."
+        many: "%{count} organizacji. Wszystkie mają administratora i wolne miejsca."
+        other: "%{count} organizacji. Wszystkie mają administratora i wolne miejsca."
+      create: "Utwórz organizację"
+      organizations: "Organizacje"
+      admins:
+        one: "%{count} administrator"
+        few: "%{count} administratorów"
+        many: "%{count} administratorów"
+        other: "%{count} administratorów"
+      pending_admins:
+        one: "%{count} zaproszenie czeka"
+        few: "%{count} zaproszenia czekają"
+        many: "%{count} zaproszeń czeka"
+        other: "%{count} zaproszeń czeka"
+      all_organizations: "Wszystkie organizacje"
+      attention: "Wymaga uwagi"
+      no_admin: "Brak administratora"
+      add: "Dodaj"
+      no_free_seats: "Brak wolnych miejsc"
+      free_seats:
+        one: "Zostało %{count} miejsce"
+        few: "Zostały %{count} miejsca"
+        many: "Zostało %{count} miejsc"
+        other: "Zostało %{count} miejsca"
+      limit: "Limit"
+      fine_title: "Wszystko w porządku"
+      fine_body: "Każda organizacja ma administratora i wolne miejsca."
+      how_title: "Jak to działa"
+      how_body: "Każdy, kto zaloguje się przez USOS, trafia do organizacji %{usos}. Nie ma ona limitu miejsc i nie można jej usunąć. Do pozostałych organizacji konta dodają ich administratorzy."
+      empty_title: "Zacznij od pierwszej organizacji"
+      empty_lead: "Ustaw limit kont i dodaj administratora — on zaprosi resztę osób."
+
+    # Dashboard::OrganizationAdmin and home/_organization_admin_start.
+    organization_admin_start:
+      tiles:
+        students: "Studenci"
+        teachers: "Nauczyciele"
+        free: "Wolne miejsca"
+        no_limit: "Bez limitu"
+        of_max: "z %{max}"
+        pending: "Oczekujące zaproszenia"
+      stats_label: "Podsumowanie organizacji"
+      no_organization: "Twoje konto administratora nie jest przypisane do żadnej organizacji. Skontaktuj się z administratorem systemu."
+      full_lead: "Organizacja nie ma wolnych miejsc — nowe osoby nie dołączą, dopóki ktoś nie zostanie usunięty albo limit nie wzrośnie."
+      pending_lead:
+        one: "%{count} osoba jeszcze nie przyjęła zaproszenia."
+        few: "%{count} osoby jeszcze nie przyjęły zaproszenia."
+        many: "%{count} osób jeszcze nie przyjęło zaproszenia."
+        other: "%{count} osoby jeszcze nie przyjęły zaproszenia."
+      users: "Użytkownicy"
+      add_user: "Dodaj użytkownika"
+      recent: "Ostatnio dodani"
+      invited: "Zaproszenie wysłane"
+      added: "Dodano %{when}"
+      all_users: "Wszyscy użytkownicy"
+      nobody: "Nikogo tu jeszcze nie ma. Dodaj studentów i nauczycieli albo poczekaj, aż zalogują się przez uczelnię."
+      seats: "Miejsca"
+      unlimited_note: "Ta organizacja nie ma limitu miejsc. Każdy, kto zaloguje się przez USOS, trafia tutaj automatycznie."
+      limited_note: "Limit ustala administrator systemu. Każde konto, także administratora, zajmuje jedno miejsce."
+      pending_title: "Czeka na przyjęcie zaproszenia"
+
+    # TeacherStartDashboard::DAYS
+    days:
+      today: "Dziś"
+      yesterday: "Wczoraj"
+      earlier: "Wcześniej"
+
+    teacher_start:
+      greeting: "Dzień dobry, %{name}"
+      recent_lead: "Od wczoraj studenci kupili %{items} %{groups}."
+      recent_items:
+        one: "%{count} przedmiot"
+        few: "%{count} przedmioty"
+        many: "%{count} przedmiotów"
+        other: "%{count} przedmiotu"
+      recent_groups:
+        one: "w %{count} grupie"
+        few: "w %{count} grupach"
+        many: "w %{count} grupach"
+        other: "w %{count} grupy"
+      quiet_lead: "Od wczoraj nikt nic nie kupił. Zajrzyj do swoich grup poniżej."
+      no_groups_lead: "Nie prowadzisz jeszcze żadnej grupy. Utwórz pierwszą, żeby zacząć."
+      purchases: "Ostatnie zakupy"
+      filter: "Pokaż zakupy z grupy"
+      all_groups: "Wszystkie grupy"
+      removed_item: "Przedmiot usunięty z oferty"
+      no_group_purchases: "W tej grupie nie ma jeszcze żadnych zakupów."
+      no_purchases: "Nikt jeszcze niczego nie kupił. Zakupy pojawią się tutaj same."
+      pending: "Czeka na ocenę"
+      pending_left: "Zostało %{categories} dla %{students}."
+      pending_categories:
+        one: "%{count} kategoria"
+        few: "%{count} kategorie"
+        many: "%{count} kategorii"
+        other: "%{count} kategorii"
+      pending_students:
+        one: "%{count} studenta"
+        few: "%{count} studentów"
+        many: "%{count} studentów"
+        other: "%{count} studenta"
+      grade: "Oceń"
+      your_groups: "Twoje grupy"
+      group_meta: "%{role}, %{students}"
+      students:
+        one: "%{count} student"
+        few: "%{count} studentów"
+        many: "%{count} studentów"
+        other: "%{count} studenta"
+      new_purchases:
+        one: "%{count} nowy zakup"
+        few: "%{count} nowe zakupy"
+        many: "%{count} nowych zakupów"
+        other: "%{count} nowego zakupu"
+      no_groups: "Nie prowadzisz jeszcze żadnej grupy."
+      create_group: "Utwórz grupę"
+
+    student_start:
+      greeting: "Cześć, %{name}"
+      groups_lead:
+        one: "Należysz do %{count} grupy. Waluta, rangi i odznaki są osobne w każdej z nich."
+        few: "Należysz do %{count} grup. Waluta, rangi i odznaki są osobne w każdej z nich."
+        many: "Należysz do %{count} grup. Waluta, rangi i odznaki są osobne w każdej z nich."
+        other: "Należysz do %{count} grupy. Waluta, rangi i odznaki są osobne w każdej z nich."
+      no_groups_lead: "Nie należysz jeszcze do żadnej grupy. Poproś prowadzącego o kod i dołącz poniżej."
+      fresh: "Dopiero zaczynasz. Pierwsze %{currency} zdobędziesz na zajęciach."
+      to_spend: "Do wydania"
+      lives: "Życia"
+      rank: "Ranga:"
+      no_rank: "brak"
+      to_next: "%{total} z %{needed} do rangi %{rank}"
+      top: "%{total} zebranych. To najwyższa ranga."
+      progress_label: "Postęp do następnej rangi w grupie %{name}"
+      badges: "Odznaki"
+      badges_of: "z %{total}"
+      open_group: "Otwórz grupę"
+      shop: "Sklep"
+      have_code: "Masz kod od prowadzącego?"
+      code_hint: "Kod ma 6 znaków. Możesz też zeskanować kod QR aparatem telefonu."
+      join: "Dołącz do grupy"
+      feed: "Ostatnio we wszystkich grupach"
+      feed_meta: "%{group}, %{when}"
+
+  notifications:
+    panel:
+      title: "Powiadomienia"
+      mark_all: "Oznacz wszystkie"
+      new: "Nowe"
+      earlier: "Wcześniej"
+      empty: "Brak powiadomień."
+    notification:
+      purchase: "Zakup: %{name}"
+      meta: "%{group}, %{when}"
+      unread: "nowe"
diff --git a/config/locales/views/invitation_mailer.en.yml b/config/locales/views/invitation_mailer.en.yml
new file mode 100644
index 00000000..2a56315c
--- /dev/null
+++ b/config/locales/views/invitation_mailer.en.yml
@@ -0,0 +1,19 @@
+en:
+  invitation_mailer:
+    roles:
+      admin: "an administrator"
+      member: "a member"
+    invitation_email:
+      subject: "Invitation to Gamification Hub"
+      lead: "You've been added as %{role} of the organization %{organization} in Gamification Hub."
+
+  # shared/_invitation_email.{html,text}
+  shared:
+    invitation_email:
+      title: "Invitation"
+      text: "Click the button below to finish setting up your account and fill in your details."
+      text_plain: "To finish setting up your account and fill in your details, open the link below."
+      button: "Finish setting up your account"
+      note: "The link is valid for 7 days. If the button doesn't work, copy this address into your browser:"
+      valid_for: "The link is valid for 7 days."
+      footer: "If you weren't expecting this invitation, you can ignore this message."
diff --git a/config/locales/views/invitation_mailer.pl.yml b/config/locales/views/invitation_mailer.pl.yml
new file mode 100644
index 00000000..aa52f12d
--- /dev/null
+++ b/config/locales/views/invitation_mailer.pl.yml
@@ -0,0 +1,19 @@
+pl:
+  invitation_mailer:
+    roles:
+      admin: "administrator"
+      member: "członek"
+    invitation_email:
+      subject: "Zaproszenie do systemu GamificationHub"
+      lead: "Zostałeś dodany jako %{role} organizacji %{organization} w Gamification Hub."
+
+  # shared/_invitation_email.{html,text}
+  shared:
+    invitation_email:
+      title: "Zaproszenie"
+      text: "Kliknij przycisk poniżej, aby dokończyć zakładanie konta i uzupełnić swoje dane."
+      text_plain: "Aby dokończyć zakładanie konta i uzupełnić swoje dane, otwórz poniższy link."
+      button: "Dokończ zakładanie konta"
+      note: "Link jest ważny przez 7 dni. Jeśli przycisk nie działa, skopiuj ten adres do przeglądarki:"
+      valid_for: "Link jest ważny przez 7 dni."
+      footer: "Jeśli nie spodziewałeś się tego zaproszenia, możesz zignorować tę wiadomość."
diff --git a/config/locales/views/items.en.yml b/config/locales/views/items.en.yml
new file mode 100644
index 00000000..6855a55e
--- /dev/null
+++ b/config/locales/views/items.en.yml
@@ -0,0 +1,156 @@
+en:
+  items:
+    flash:
+      created: "Added “%{name}” to the shop."
+      updated: "Saved “%{name}”. Changes apply to new purchases."
+      destroyed: "Removed “%{name}” from the shop. Copies already bought stay with the students."
+
+    helpers:
+      nobody_bought: "Nobody has bought it yet"
+      bought:
+        one: "Bought %{count} time"
+        other: "Bought %{count} times"
+      name_placeholder: "Item name"
+      rules_placeholder: "What it gives the student…"
+      unlock_option_rank: "from the %{name} rank"
+      unlock_option_everyone: "any student"
+      discount_option_rank: "from %{name} (−%{discount}% and more)"
+      discount_option_none: "none"
+
+    # Sentences built by ItemsHelper and, live, by item_form_controller.ts.
+    # %{...} slots in bold are names and numbers; the rest are fragments below.
+    sentences:
+      unlock_everyone: "Any student can buy this item%{lives}"
+      unlock_restricted: "Only students%{rank}%{badges} can buy it%{lives}"
+      unlock_rank: " with the %{rank} rank or higher"
+      unlock_badges:
+        one: " who have the %{badges} badge"
+        other: " who have all the badges %{badges}"
+      lives_yes: ", even at 0 lives."
+      lives_no: " if they have at least 1 life."
+      no_discount: "No discounts. Every buyer pays %{price}."
+      example: "For example: a student%{holder} saves %{percent} and pays %{paid} instead of %{price}."
+      max: "At most: a student%{holder} gets a %{percent} discount."
+      holder_rank: " with the %{rank} rank"
+      holder_badges:
+        one: "the %{badges} badge"
+        other: "the badges %{badges}"
+      holder_all_badges: "all the badges"
+      holder_join_and: " and %{phrase}"
+      holder_join_with: " with %{phrase}"
+      warn_cap: "The discounts add up to %{raw}%, but the shop takes off at most %{cap}%. The excess is lost — consider lower discounts on ranks and badges."
+      warn_rank_everyone: "The rank discount will apply to every buyer."
+      warn_rank_gate: "Only students from the %{rank} rank can buy it, so the rank discount will apply to every buyer."
+      warn_badge_required: "The %{name} badge is required to buy it, so its discount will apply to every buyer."
+
+    # ItemCard, ItemOffer and RequirementPhrasing (shared with the shop).
+    labels:
+      discount_up_to: "Discounts up to −%{discount}%"
+      discount: "−%{discount}% %{source}"
+      source_rank_and_badges: "for rank and badges"
+      source_rank: "for rank"
+      source_badges: "for badges"
+      lock_rank: "From the %{name} rank"
+      seal_rank: "From the %{name} rank"
+      seal_badge: "For the %{name} badge"
+      seal_lives: "Unavailable at 0 lives"
+      requires_rank: "Requires the rank"
+      requires_badge: "Requires the badge"
+      requires_life: "You have 0 lives. Get a life back first."
+
+    index:
+      title: "Items"
+      lead:
+        one: "%{count} item in the shop, cheapest first."
+        other: "%{count} items in the shop, cheapest first."
+      new: "New item"
+      empty_title: "The shop is still empty"
+      empty_body: "Add items so the collected currency has something to go to. Each can have requirements and discounts, so the shop opens up gradually as students progress."
+
+    new:
+      page_title: "New item"
+
+    edit:
+      page_title: "Edit item - %{name}"
+
+    grid_card:
+      discount: "Discount"
+      zero_lives: "At 0 lives"
+      edit_label: "Edit item %{name}"
+
+    card:
+      zero_lives: "Works at 0 lives"
+      buy: "Buy for %{price}"
+      collect_more: "Collect"
+      progress_label: "Progress to the %{rank} rank"
+
+    preview:
+      summary: "Card preview"
+      students_view: "This is what students will see"
+      state: "Card state"
+      afford: "Available"
+      save: "Saving up"
+      sealed: "Sealed"
+      seal_hint: "Without requirements an item is never sealed."
+      thumb: "Thumbnail in notifications"
+      thumb_sample: "Student purchase, today 10:21"
+
+    form:
+      breadcrumb: "Items"
+      new_title: "New item"
+      edit_title: "Edit item"
+      new_lead: "Fill in the card, and the preview will show how students will see it."
+      edit_lead: "The preview shows the card after your changes."
+      owners:
+        one: "%{count} student has this item."
+        other: "%{count} students have this item."
+      owners_note: "Changes to the price, requirements and discounts only apply to new purchases."
+      card: "Item card"
+      card_hint: "This is how the item looks in the shop and in the student's inventory."
+      name_placeholder: "e.g. Quiz retake"
+      rules: "What it gives the student"
+      rules_placeholder: "e.g. A chance to retake a quiz"
+      rules_hint: "Didactic description: a concrete benefit, no story."
+      story: "Story description"
+      story_placeholder: "e.g. The ship's emergency return to base"
+      price_section: "Price"
+      price: "Price"
+      zero_lives: "Can be bought at 0 lives"
+      zero_lives_hint: "Useful for items that restore a life."
+      who_section: "Who can buy it"
+      who_hint: "Without requirements the item is available to everyone."
+      who: "Can be bought by"
+      who_label: "Who can buy it"
+      required_badges: "Required badges"
+      add_badge: "Add a badge…"
+      no_badges: "This group has no badges yet."
+      discounts_section: "Discounts"
+      discounts_hint: "A rank discount is the percentage assigned to the student's rank. Badge discounts add up. Meeting any one condition is enough for the discount to apply — with no conditions every buyer gets it. The amount is always worked out from the student's rank and all their badges, including those not chosen here."
+      rank_discount: "Rank discount"
+      badge_discount: "Badge discount"
+      discount_badges: "Badges with a discount"
+      add_discount_badge: "Add a badge with a discount…"
+      removal_hint: "The item will disappear from the shop and from lists. Students who bought it still have it, and it stays in their history as “Removed from the shop”."
+      remove: "Delete item"
+      create: "Add item"
+
+    confirm_destroy:
+      page_title: "Delete item %{name}"
+      title: "Remove “%{name}” from the shop?"
+      body: "The item will disappear from the shop and from lists. Students who bought it keep it, and it will be marked “Removed from the shop” in their history."
+      owners:
+        one: "%{count} student has this item and will keep it after it's removed."
+        other: "%{count} students have this item and will keep it after it's removed."
+      remove: "Remove from the shop"
+
+  activerecord:
+    errors:
+      models:
+        item:
+          attributes:
+            name:
+              blank: "Enter the item name."
+            didactic_description:
+              blank: "Describe what the item gives the student."
+            price:
+              too_low: "The price must be at least 1."
diff --git a/config/locales/views/items.pl.yml b/config/locales/views/items.pl.yml
new file mode 100644
index 00000000..f3a129b8
--- /dev/null
+++ b/config/locales/views/items.pl.yml
@@ -0,0 +1,164 @@
+pl:
+  items:
+    flash:
+      created: "Dodano przedmiot „%{name}” do sklepu."
+      updated: "Zapisano „%{name}”. Zmiany dotyczą nowych zakupów."
+      destroyed: "Usunięto „%{name}” z oferty. Kupione egzemplarze zostają u studentów."
+
+    helpers:
+      nobody_bought: "Jeszcze nikt nie kupił"
+      bought:
+        one: "Kupiono %{count} raz"
+        few: "Kupiono %{count} razy"
+        many: "Kupiono %{count} razy"
+        other: "Kupiono %{count} razy"
+      name_placeholder: "Nazwa przedmiotu"
+      rules_placeholder: "Co daje studentowi…"
+      unlock_option_rank: "od rangi %{name}"
+      unlock_option_everyone: "każdy student"
+      discount_option_rank: "od %{name} (−%{discount}% i więcej)"
+      discount_option_none: "brak"
+
+    # Sentences built by ItemsHelper and, live, by item_form_controller.ts.
+    # %{...} slots in bold are names and numbers; the rest are fragments below.
+    sentences:
+      unlock_everyone: "Każdy student może kupić ten przedmiot%{lives}"
+      unlock_restricted: "Kupią tylko studenci%{rank}%{badges}%{lives}"
+      unlock_rank: " z rangą %{rank} lub wyższą"
+      unlock_badges:
+        one: ", którzy mają odznakę %{badges}"
+        other: ", którzy mają wszystkie odznaki %{badges}"
+      lives_yes: ". Także przy 0 życiach."
+      lives_no: ", jeśli mają co najmniej 1 życie."
+      no_discount: "Bez zniżek. Każdy kupujący zapłaci %{price}."
+      example: "Przykładowo: student%{holder} zaoszczędzi %{percent} i zapłaci %{paid} zamiast %{price}."
+      max: "Maksymalnie: student%{holder} uzyska zniżkę %{percent}."
+      holder_rank: " z rangą %{rank}"
+      holder_badges:
+        one: "odznaką %{badges}"
+        other: "odznakami %{badges}"
+      holder_all_badges: "wszystkimi odznakami"
+      holder_join_and: " oraz %{phrase}"
+      holder_join_with: " z %{phrase}"
+      warn_cap: "Zniżki sumują się do %{raw}%, a sklep odejmie najwyżej %{cap}%. Nadwyżka przepada — rozważ niższe zniżki przy rangach i odznakach."
+      warn_rank_everyone: "Zniżka dla rang obejmie każdego kupującego."
+      warn_rank_gate: "Kupić mogą tylko studenci od rangi %{rank}, więc zniżka dla rang obejmie każdego kupującego."
+      warn_badge_required: "Odznaka %{name} jest wymagana do zakupu, więc jej zniżka obejmie każdego kupującego."
+
+    # ItemCard, ItemOffer and RequirementPhrasing (shared with the shop).
+    labels:
+      discount_up_to: "Zniżki do −%{discount}%"
+      discount: "−%{discount}% %{source}"
+      source_rank_and_badges: "za rangę i odznaki"
+      source_rank: "za rangę"
+      source_badges: "za odznaki"
+      lock_rank: "Od rangi %{name}"
+      seal_rank: "Od rangi %{name}"
+      seal_badge: "Za odznakę %{name}"
+      seal_lives: "Niedostępne przy 0 życiach"
+      requires_rank: "Wymaga rangi"
+      requires_badge: "Wymaga odznaki"
+      requires_life: "Masz 0 żyć. Najpierw odzyskaj życie."
+
+    index:
+      title: "Przedmioty"
+      lead:
+        one: "%{count} przedmiot w sklepie, od najtańszego."
+        few: "%{count} przedmioty w sklepie, od najtańszego."
+        many: "%{count} przedmiotów w sklepie, od najtańszego."
+        other: "%{count} przedmiotu w sklepie, od najtańszego."
+      new: "Nowy przedmiot"
+      empty_title: "Sklep jest jeszcze pusty"
+      empty_body: "Dodaj przedmioty, żeby zebrana waluta miała na co iść. Każdy może mieć wymagania i zniżki, więc sklep otwiera się stopniowo wraz z postępami."
+
+    new:
+      page_title: "Nowy przedmiot"
+
+    edit:
+      page_title: "Edytuj przedmiot - %{name}"
+
+    grid_card:
+      discount: "Zniżka"
+      zero_lives: "Przy 0 życiach"
+      edit_label: "Edytuj przedmiot %{name}"
+
+    card:
+      zero_lives: "Działa przy 0 życiach"
+      buy: "Kup za %{price}"
+      collect_more: "Zbierz jeszcze"
+      progress_label: "Postęp do rangi %{rank}"
+
+    preview:
+      summary: "Podgląd karty"
+      students_view: "Tak zobaczą to studenci"
+      state: "Stan karty"
+      afford: "Dostępny"
+      save: "Zbierasz"
+      sealed: "Zapieczętowany"
+      seal_hint: "Bez wymagań przedmiot nigdy nie będzie zapieczętowany."
+      thumb: "Miniatura w powiadomieniach"
+      thumb_sample: "Zakup studenta, dziś 10:21"
+
+    form:
+      breadcrumb: "Przedmioty"
+      new_title: "Nowy przedmiot"
+      edit_title: "Edytuj przedmiot"
+      new_lead: "Wypełnij kartę, a podgląd obok pokaże, jak zobaczą ją studenci."
+      edit_lead: "Podgląd obok pokazuje kartę po zmianach."
+      owners:
+        one: "%{count} student ma ten przedmiot."
+        few: "%{count} studentów ma ten przedmiot."
+        many: "%{count} studentów ma ten przedmiot."
+        other: "%{count} studenta ma ten przedmiot."
+      owners_note: "Zmiany ceny, wymagań i zniżek dotyczą tylko nowych zakupów."
+      card: "Karta przedmiotu"
+      card_hint: "Tak przedmiot wygląda w sklepie i w ekwipunku studenta."
+      name_placeholder: "np. Poprawa wejściówki"
+      rules: "Co daje studentowi"
+      rules_placeholder: "np. Możliwość ponownego napisania wejściówki"
+      rules_hint: "Opis dydaktyczny: konkretna korzyść, bez fabuły."
+      story: "Opis fabularny"
+      story_placeholder: "np. Awaryjny powrót statku do bazy"
+      price_section: "Cena"
+      price: "Cena"
+      zero_lives: "Można kupić przy 0 życiach"
+      zero_lives_hint: "Przydaje się dla przedmiotów, które przywracają życie."
+      who_section: "Kto może kupić"
+      who_hint: "Bez wymagań przedmiot jest dostępny dla wszystkich."
+      who: "Kupić może"
+      who_label: "Kto może kupić"
+      required_badges: "Wymagane odznaki"
+      add_badge: "Dodaj odznakę…"
+      no_badges: "W tej grupie nie ma jeszcze odznak."
+      discounts_section: "Zniżki"
+      discounts_hint: "Zniżka z rangi to procent przypisany do rangi studenta. Zniżki z odznak się sumują. Wystarczy spełnić jeden z warunków, żeby zniżka zadziałała — bez warunków dostaje ją każdy kupujący. Wysokość liczy się zawsze z rangi i wszystkich odznak studenta, także tych niewybranych tutaj."
+      rank_discount: "Zniżka dla rang"
+      badge_discount: "Zniżka za odznaki"
+      discount_badges: "Odznaki ze zniżką"
+      add_discount_badge: "Dodaj odznakę ze zniżką…"
+      removal_hint: "Przedmiot zniknie ze sklepu i z list. Studenci, którzy go kupili, nadal go mają, a w ich historii zostanie jako „Usunięty z oferty”."
+      remove: "Usuń przedmiot"
+      create: "Dodaj przedmiot"
+
+    confirm_destroy:
+      page_title: "Usuń przedmiot %{name}"
+      title: "Usunąć „%{name}” ze sklepu?"
+      body: "Przedmiot zniknie ze sklepu i z list. Studenci, którzy go kupili, zachowają go, a w historii zostanie oznaczony jako „Usunięty z oferty”."
+      owners:
+        one: "%{count} student ma ten przedmiot i zachowa go po usunięciu."
+        few: "%{count} studentów ma ten przedmiot i zachowa go po usunięciu."
+        many: "%{count} studentów ma ten przedmiot i zachowa go po usunięciu."
+        other: "%{count} studenta ma ten przedmiot i zachowa go po usunięciu."
+      remove: "Usuń z oferty"
+
+  activerecord:
+    errors:
+      models:
+        item:
+          attributes:
+            name:
+              blank: "Podaj nazwę przedmiotu."
+            didactic_description:
+              blank: "Napisz, co przedmiot daje studentowi."
+            price:
+              too_low: "Cena musi wynosić co najmniej 1."
diff --git a/config/locales/views/join.en.yml b/config/locales/views/join.en.yml
new file mode 100644
index 00000000..f75eb19f
--- /dev/null
+++ b/config/locales/views/join.en.yml
@@ -0,0 +1,43 @@
+en:
+  join:
+    # InviteLookup::Result#error
+    errors:
+      missing: "Enter the invite code."
+      not_found: "We couldn't find that code. Check it with your teacher."
+      expired: "This code has expired. Ask your teacher for a new one."
+      exhausted: "The maximum number of people have already used this code. Ask your teacher for a new one."
+
+    new:
+      page_title: "Join a group"
+
+    show:
+      page_title: "Join a group"
+
+    create:
+      page_title: "Joined the group"
+
+    step_code:
+      step: "Step 1 of 2"
+      title: "Join a group"
+      hint: "Enter the 6-character code your teacher gave you."
+      code_label: "Invite code"
+      slot_label: "Character %{index} of %{total}"
+      member: "You're already in this group."
+      open_group: "Open the group"
+      qr_hint: "Got a QR code? Scan it with your phone's camera and the code fills in by itself."
+
+    step_nickname:
+      step: "Step 2 of 2"
+      title: "You're joining the group %{name}"
+      hint: "In this group others will see you under a nickname — in the ranking too. You can change it later in the group settings."
+      nickname: "Nickname in this group"
+      nickname_hint: "Leave it empty to use your full name. You can set a nickname later."
+      join: "Join the group"
+
+    step_done:
+      title: "Joined the group %{name}"
+      led_by: "Led by %{name}."
+      you_are_html: "You're there as %{name}."
+      currency: "The currency in this group is %{currency}."
+      done: "Done"
+
diff --git a/config/locales/views/join.pl.yml b/config/locales/views/join.pl.yml
new file mode 100644
index 00000000..8b272d20
--- /dev/null
+++ b/config/locales/views/join.pl.yml
@@ -0,0 +1,43 @@
+pl:
+  join:
+    # InviteLookup::Result#error
+    errors:
+      missing: "Podaj kod zaproszenia."
+      not_found: "Nie znaleźliśmy takiego kodu. Sprawdź go z prowadzącym."
+      expired: "Ten kod wygasł. Poproś prowadzącego o nowy."
+      exhausted: "Z tego kodu skorzystała już maksymalna liczba osób. Poproś prowadzącego o nowy."
+
+    new:
+      page_title: "Dołącz do grupy"
+
+    show:
+      page_title: "Dołącz do grupy"
+
+    create:
+      page_title: "Dołączono do grupy"
+
+    step_code:
+      step: "Krok 1 z 2"
+      title: "Dołącz do grupy"
+      hint: "Wpisz 6-znakowy kod, który podał prowadzący."
+      code_label: "Kod zaproszenia"
+      slot_label: "Znak %{index} z %{total}"
+      member: "Już należysz do tej grupy."
+      open_group: "Otwórz grupę"
+      qr_hint: "Masz kod QR? Zeskanuj go aparatem telefonu, a kod wpisze się sam."
+
+    step_nickname:
+      step: "Krok 2 z 2"
+      title: "Dołączasz do grupy %{name}"
+      hint: "W tej grupie inni zobaczą Cię pod pseudonimem — także w rankingu. Możesz go później zmienić w ustawieniach w grupie."
+      nickname: "Pseudonim w tej grupie"
+      nickname_hint: "Zostaw puste, jeśli chcesz używać imienia i nazwiska. Pseudonim możesz ustawić później."
+      join: "Dołącz do grupy"
+
+    step_done:
+      title: "Dołączono do grupy %{name}"
+      led_by: "Prowadzi %{name}."
+      you_are_html: "Jesteś tam jako %{name}."
+      currency: "Walutą w tej grupie są %{currency}."
+      done: "Gotowe"
+
diff --git a/config/locales/views/layouts.en.yml b/config/locales/views/layouts.en.yml
new file mode 100644
index 00000000..f8b72563
--- /dev/null
+++ b/config/locales/views/layouts.en.yml
@@ -0,0 +1,89 @@
+en:
+  layouts:
+    # Navigation (app/values/navigation.rb) — sidebar, deck, tab bar.
+    navigation:
+      start: "Home"
+      groups: "Groups"
+      notifications: "Notifications"
+      overview: "Overview"
+      students: "Students"
+      sheets: "Grade sheets"
+      items: "Items"
+      ranks: "Ranks"
+      badges: "Badges"
+      ranking: "Ranking"
+      invites: "Invites"
+      teachers: "Teachers"
+      settings: "Group settings"
+      shop: "Shop"
+      my_items: "My items"
+      history: "Currency history"
+      membership: "Group settings"
+      organizations: "Organizations"
+      short:
+        organization: "Organization"
+        sheets: "Sheets"
+        my_items: "Items"
+
+    # GroupChrome#role_label
+    chrome_roles:
+      own: "You lead this group"
+      sup: "You assist this group"
+      lrn: "You're a participant"
+      adm: "You oversee this group"
+
+    theme:
+      light: "Light theme"
+      dark: "Dark theme"
+      toggle: "Toggle theme"
+
+    header:
+      home: "Gamification Hub, home"
+      switch_group: "Group %{name}, switch group"
+      balance_title: "%{balance} to spend, %{total} collected in total"
+      balance_label: "You have %{balance} to spend, show currency history"
+      to_spend: "to spend"
+      join: "Join a group"
+      notifications: "Notifications"
+      notifications_unread:
+        one: "Notifications, %{count} new"
+        other: "Notifications, %{count} new"
+      account: "Account: %{name}"
+
+    sidebar:
+      main: "Main"
+      your_groups: "Your groups"
+      expand: "Expand"
+      collapse: "Collapse panel"
+
+    tab_bar:
+      label: "Navigation"
+
+    deck:
+      group: "Group %{name}"
+      switch: "Switch group"
+      sections: "Group sections"
+
+    group_switcher:
+      title: "Switch group"
+      here: "You're here"
+      join: "Join a group"
+
+    more_sheet:
+      create_group: "Create a group"
+      account: "Account"
+      account_settings: "Account settings"
+      logout: "Log out"
+
+    account_menu:
+      label: "Account"
+      account_settings: "Account settings"
+      logout: "Log out"
+
+    theme_toggle:
+      help: "Help:"
+      contact: "contact"
+
+    locale_switcher:
+      switch_to: "Polski"
+      label: "Switch language to Polish"
diff --git a/config/locales/views/layouts.pl.yml b/config/locales/views/layouts.pl.yml
new file mode 100644
index 00000000..19d3eecf
--- /dev/null
+++ b/config/locales/views/layouts.pl.yml
@@ -0,0 +1,92 @@
+pl:
+  layouts:
+    # Navigation (app/values/navigation.rb) — sidebar, deck, tab bar.
+    navigation:
+      start: "Start"
+      groups: "Grupy"
+      notifications: "Powiadomienia"
+      overview: "Przegląd"
+      students: "Studenci"
+      sheets: "Arkusze ocen"
+      items: "Przedmioty"
+      ranks: "Rangi"
+      badges: "Odznaki"
+      ranking: "Ranking"
+      invites: "Zaproszenia"
+      teachers: "Nauczyciele"
+      settings: "Ustawienia grupy"
+      shop: "Sklep"
+      my_items: "Moje przedmioty"
+      history: "Historia waluty"
+      membership: "Ustawienia w grupie"
+      organizations: "Organizacje"
+      short:
+        organization: "Organizacja"
+        sheets: "Arkusze"
+        my_items: "Przedmioty"
+
+    # GroupChrome#role_label
+    chrome_roles:
+      own: "Prowadzisz tę grupę"
+      sup: "Wspierasz tę grupę"
+      lrn: "Jesteś uczestnikiem"
+      adm: "Nadzorujesz tę grupę"
+
+    theme:
+      light: "Jasny motyw"
+      dark: "Ciemny motyw"
+      toggle: "Przełącz motyw"
+
+    header:
+      home: "Gamification Hub, start"
+      switch_group: "Grupa %{name}, zmień grupę"
+      balance_title: "%{balance} do wydania, %{total} zebrane łącznie"
+      balance_label: "Masz %{balance} do wydania, pokaż historię waluty"
+      to_spend: "do wydania"
+      join: "Dołącz do grupy"
+      notifications: "Powiadomienia"
+      notifications_unread:
+        one: "Powiadomienia, %{count} nowe"
+        few: "Powiadomienia, %{count} nowe"
+        many: "Powiadomienia, %{count} nowych"
+        other: "Powiadomienia, %{count} nowego"
+      account: "Konto: %{name}"
+
+    sidebar:
+      main: "Główna"
+      your_groups: "Twoje grupy"
+      expand: "Rozwiń"
+      collapse: "Zwiń panel"
+
+    tab_bar:
+      label: "Nawigacja"
+
+    deck:
+      group: "Grupa %{name}"
+      switch: "Zmień grupę"
+      sections: "Sekcje grupy"
+
+    group_switcher:
+      title: "Zmień grupę"
+      here: "Tu jesteś"
+      join: "Dołącz do grupy"
+
+    more_sheet:
+      create_group: "Utwórz grupę"
+      account: "Konto"
+      account_settings: "Ustawienia konta"
+      logout: "Wyloguj się"
+
+    account_menu:
+      label: "Konto"
+      account_settings: "Ustawienia konta"
+      logout: "Wyloguj się"
+
+
+    theme_toggle:
+      help: "Pomoc:"
+      contact: "kontakt"
+
+    locale_switcher:
+      switch_to: "English"
+      label: "Zmień język na angielski"
diff --git a/config/locales/views/organizations.en.yml b/config/locales/views/organizations.en.yml
new file mode 100644
index 00000000..f896cf1c
--- /dev/null
+++ b/config/locales/views/organizations.en.yml
@@ -0,0 +1,185 @@
+en:
+  organizations:
+    flash:
+      created: "Organization created."
+      updated: "Organization updated."
+      destroyed: "Deleted organization %{name}."
+      admin_added: "Organization administrator added. An invitation has been sent by e-mail."
+      user_added: "User added to the organization. An invitation has been sent by e-mail."
+      admin_removed: "Deleted administrator: %{name}."
+      user_updated: "Changes saved: %{name}."
+      user_removed: "Deleted user: %{name}."
+      invitation_resent: "Invitation sent again: %{email}."
+      too_many_resends: "The invitation has already been sent several times. Try again in a few minutes."
+
+    # OrganizationsHelper#user_role_label — a role not listed here is humanized.
+    roles:
+      student: "Student"
+      teacher: "Teacher"
+
+    helpers:
+      capacity_accounts:
+        one: "%{count} account"
+        other: "%{count} accounts"
+      capacity_free:
+        one: "%{count} free"
+        other: "%{count} free"
+      capacity_unlimited: "%{accounts} · no seat limit"
+      capacity_limited: "%{members} of %{max} seats taken · %{free}"
+
+    index:
+      title: "Organizations"
+      lead: "Universities using the app. Accounts that sign in through USOS go to the organization %{usos}."
+      create: "Create organization"
+      organization: "Organization"
+      members: "Members"
+      admins: "Administrators"
+      empty_title: "There are no organizations yet"
+      empty_lead: "Create an organization, then add its administrator — they'll invite everyone else."
+
+    show:
+      breadcrumb: "Organizations"
+      edit: "Edit"
+      add_admin: "Add an administrator"
+      add_user: "Add a user"
+      danger_title: "Delete the organization"
+      danger_body: "All of its accounts will disappear along with the organization. This can't be undone."
+      danger_button: "Delete the organization"
+
+    admins:
+      title: "Administrators"
+      role: "Administrator"
+      invited: "Invitation sent"
+      none: "The organization has no administrator yet."
+      remove: "Delete"
+      remove_label: "Delete: %{name}"
+      confirm_destroy:
+        page_title: "Delete the administrator?"
+        title: "Delete the administrator %{name}?"
+        body: "The account will be deleted permanently and one seat in the organization will be freed."
+        pending: "The invitation that was sent will stop working."
+        remove: "Delete the account"
+
+    members:
+      search_placeholder: "Search by name or e-mail"
+      search_label: "Search for a user"
+      all_roles: "All roles"
+      filter_label: "Filter by role"
+      of: "of"
+      user: "User"
+      role: "Role"
+      index_number: "Index number"
+      actions: "Actions"
+      no_match: "No users match"
+      no_match_hint: "Clear the search, change the role or check the spelling."
+      empty_title: "There are no users yet"
+      empty_lead: "Add students and teachers — they'll get an invitation by e-mail. Accounts created by signing in through the university show up here on their own."
+
+    member_row:
+      invited: "Invitation sent"
+      index_number: "Index number"
+      role: "Role"
+      edit: "Edit"
+      edit_label: "Edit: %{name}"
+      remove: "Delete"
+      remove_label: "Delete: %{name}"
+
+    resend_invitation_button:
+      title: "Resend the invitation"
+      label: "Resend the invitation: %{name}"
+
+    owned_groups_notice:
+      lead:
+        one: "The group led by this account will be deleted too:"
+        other: "The groups led by this account will be deleted too:"
+      rest: "— along with all students, currency, badges and grade sheets."
+
+    form:
+      new_title: "New organization"
+      edit_title: "Edit the organization"
+      usos_note: "This organization is tied to USOS: everyone who signs in through USOS lands here. It has no member limit and can't be deleted."
+      name: "Name"
+      max_members: "Member limit"
+      create: "Create organization"
+      save: "Save"
+
+    new:
+      page_title: "New organization"
+
+    edit:
+      page_title: "Edit the organization — %{name}"
+
+    new_admin:
+      page_title: "Add an organization administrator"
+
+    admin_form:
+      title: "Add an administrator"
+      hint: "We'll send an invitation to the address you enter. After the first sign-in the administrator fills in their details."
+      email: "E-mail address"
+      email_placeholder: "john.smith@example.com"
+      submit: "Send the invitation"
+
+    new_user:
+      page_title: "Add an organization user"
+
+    user_form:
+      new_title: "Add a user"
+      edit_title: "Edit the user"
+      hint: "We'll send an invitation to the address you enter. The account takes up one seat in the organization."
+      email: "E-mail address"
+      email_placeholder: "john.smith@example.com"
+      full_name: "Full name"
+      role: "Role"
+      university_number: "Index number (optional)"
+      usos_id: "USOS ID (optional)"
+      submit_new: "Send the invitation"
+      submit_edit: "Save"
+
+    users:
+      edit:
+        page_title: "Edit the user — %{name}"
+      confirm_destroy:
+        page_title: "Delete the account of %{name}?"
+        title: "Delete the account of %{name}?"
+        body: "The account will be deleted permanently, together with its group memberships, currency, badges and items. One seat in the organization will be freed."
+        remove: "Delete the account"
+
+    confirm_destroy:
+      page_title: "Delete the organization %{name}"
+      title: "Delete the organization for good?"
+      accounts:
+        one: "%{count} account will be deleted"
+        other: "%{count} accounts will be deleted"
+      accounts_tail: "along with the organization, including the administrators' accounts."
+      confirm_label: "Type the organization's name to confirm:"
+      mismatch: "The name you typed doesn't match the organization's name. The organization was not deleted."
+      remove: "Delete the organization"
+
+    dialog_actions:
+      cancel: "Cancel"
+
+  account_setups:
+    flash:
+      done: "Account set up."
+    edit:
+      page_title: "Account setup"
+      title: "Fill in your details"
+      lead: "This is a one-time step. The teachers in your groups will see your full name."
+      email: "E-mail address"
+      full_name: "Full name"
+      full_name_placeholder: "John Smith"
+      submit: "Save and continue"
+      logout: "Log out"
+
+  activerecord:
+    errors:
+      models:
+        organization:
+          attributes:
+            max_members:
+              below_members: "The limit can't be lower than the current number of members (%{count})."
+          usos_undeletable: "The organization tied to USOS can't be deleted."
+        user:
+          attributes:
+            organization:
+              member_limit: "The organization has reached its member limit."
diff --git a/config/locales/views/organizations.pl.yml b/config/locales/views/organizations.pl.yml
new file mode 100644
index 00000000..9d85ca52
--- /dev/null
+++ b/config/locales/views/organizations.pl.yml
@@ -0,0 +1,193 @@
+pl:
+  organizations:
+    flash:
+      created: "Pomyślnie utworzono organizację."
+      updated: "Pomyślnie zaktualizowano organizację."
+      destroyed: "Usunięto organizację %{name}."
+      admin_added: "Pomyślnie dodano administratora organizacji. Wysłano zaproszenie na email."
+      user_added: "Pomyślnie dodano użytkownika do organizacji. Wysłano zaproszenie na email."
+      admin_removed: "Usunięto administratora: %{name}."
+      user_updated: "Zapisano zmiany: %{name}."
+      user_removed: "Usunięto użytkownika: %{name}."
+      invitation_resent: "Wysłano ponownie zaproszenie: %{email}."
+      too_many_resends: "Zaproszenie zostało już wysłane kilka razy. Spróbuj ponownie za kilka minut."
+
+    # OrganizationsHelper#user_role_label — a role not listed here is humanized.
+    roles:
+      student: "Student"
+      teacher: "Nauczyciel"
+
+    helpers:
+      capacity_accounts:
+        one: "%{count} konto"
+        few: "%{count} konta"
+        many: "%{count} kont"
+        other: "%{count} konta"
+      capacity_free:
+        one: "%{count} wolne"
+        few: "%{count} wolne"
+        many: "%{count} wolnych"
+        other: "%{count} wolnego"
+      capacity_unlimited: "%{accounts} · bez limitu miejsc"
+      capacity_limited: "%{members} z %{max} miejsc zajętych · %{free}"
+
+    index:
+      title: "Organizacje"
+      lead: "Uczelnie korzystające z aplikacji. Konta logujące się przez USOS trafiają do organizacji %{usos}."
+      create: "Utwórz organizację"
+      organization: "Organizacja"
+      members: "Członkowie"
+      admins: "Administratorzy"
+      empty_title: "Nie ma jeszcze żadnej organizacji"
+      empty_lead: "Utwórz organizację, a potem dodaj jej administratora — on zaprosi resztę osób."
+
+    show:
+      breadcrumb: "Organizacje"
+      edit: "Edytuj"
+      add_admin: "Dodaj administratora"
+      add_user: "Dodaj użytkownika"
+      danger_title: "Usuń organizację"
+      danger_body: "Razem z organizacją znikną wszystkie jej konta. Tej operacji nie można cofnąć."
+      danger_button: "Usuń organizację"
+
+    admins:
+      title: "Administratorzy"
+      role: "Administrator"
+      invited: "Zaproszenie wysłane"
+      none: "Organizacja nie ma jeszcze administratora."
+      remove: "Usuń"
+      remove_label: "Usuń: %{name}"
+      confirm_destroy:
+        page_title: "Usunąć administratora?"
+        title: "Usunąć administratora %{name}?"
+        body: "Konto zostanie usunięte na stałe i zwolni się jedno miejsce w organizacji."
+        pending: "Wysłane zaproszenie przestanie działać."
+        remove: "Usuń konto"
+
+    members:
+      search_placeholder: "Szukaj po nazwisku lub e-mailu"
+      search_label: "Szukaj użytkownika"
+      all_roles: "Wszystkie role"
+      filter_label: "Filtruj po roli"
+      of: "z"
+      user: "Użytkownik"
+      role: "Rola"
+      index_number: "Numer indeksu"
+      actions: "Akcje"
+      no_match: "Brak użytkowników pasujących do"
+      no_match_hint: "Wyczyść wyszukiwanie, zmień rolę albo sprawdź pisownię."
+      empty_title: "Nie ma jeszcze użytkowników"
+      empty_lead: "Dodaj studentów i nauczycieli — dostaną zaproszenie e-mailem. Konta zakładane przez logowanie z uczelni pojawią się tu same."
+
+    member_row:
+      invited: "Zaproszenie wysłane"
+      index_number: "Numer indeksu"
+      role: "Rola"
+      edit: "Edytuj"
+      edit_label: "Edytuj: %{name}"
+      remove: "Usuń"
+      remove_label: "Usuń: %{name}"
+
+    resend_invitation_button:
+      title: "Wyślij zaproszenie ponownie"
+      label: "Wyślij zaproszenie ponownie: %{name}"
+
+    owned_groups_notice:
+      lead:
+        one: "Usunięta zostanie też grupa prowadzona przez to konto:"
+        few: "Usunięte zostaną też grupy prowadzone przez to konto:"
+        many: "Usunięte zostaną też grupy prowadzone przez to konto:"
+        other: "Usunięte zostaną też grupy prowadzone przez to konto:"
+      rest: "— ze wszystkimi studentami, walutą, odznakami i arkuszami ocen."
+
+    form:
+      new_title: "Nowa organizacja"
+      edit_title: "Edytuj organizację"
+      usos_note: "To organizacja powiązana z USOS: trafia do niej każdy, kto zaloguje się przez USOS. Nie ma limitu członków i nie można jej usunąć."
+      name: "Nazwa"
+      max_members: "Limit członków"
+      create: "Utwórz organizację"
+      save: "Zapisz"
+
+    new:
+      page_title: "Nowa organizacja"
+
+    edit:
+      page_title: "Edytuj organizację — %{name}"
+
+    new_admin:
+      page_title: "Dodaj administratora organizacji"
+
+    admin_form:
+      title: "Dodaj administratora"
+      hint: "Wyślemy zaproszenie na podany adres. Po pierwszym logowaniu administrator uzupełni swoje dane."
+      email: "Adres e-mail"
+      email_placeholder: "jan.nowak@example.com"
+      submit: "Wyślij zaproszenie"
+
+    new_user:
+      page_title: "Dodaj użytkownika organizacji"
+
+    user_form:
+      new_title: "Dodaj użytkownika"
+      edit_title: "Edytuj użytkownika"
+      hint: "Wyślemy zaproszenie na podany adres. Konto zajmie jedno miejsce w organizacji."
+      email: "Adres e-mail"
+      email_placeholder: "jan.nowak@example.com"
+      full_name: "Imię i nazwisko"
+      role: "Rola"
+      university_number: "Numer indeksu (opcjonalnie)"
+      usos_id: "ID USOS (opcjonalnie)"
+      submit_new: "Wyślij zaproszenie"
+      submit_edit: "Zapisz"
+
+    users:
+      edit:
+        page_title: "Edytuj użytkownika — %{name}"
+      confirm_destroy:
+        page_title: "Usunąć konto %{name}?"
+        title: "Usunąć konto %{name}?"
+        body: "Konto zostanie usunięte na stałe, razem z członkostwem w grupach, walutą, odznakami i przedmiotami. Zwolni się jedno miejsce w organizacji."
+        remove: "Usuń konto"
+
+    confirm_destroy:
+      page_title: "Usuń organizację %{name}"
+      title: "Usunąć organizację na zawsze?"
+      accounts:
+        one: "%{count} konto zostanie usunięte"
+        few: "%{count} konta zostaną usunięte"
+        many: "%{count} kont zostanie usuniętych"
+        other: "%{count} konta zostanie usuniętych"
+      accounts_tail: "razem z organizacją, w tym konta administratorów."
+      confirm_label: "Wpisz nazwę organizacji, żeby potwierdzić:"
+      mismatch: "Wpisana nazwa nie zgadza się z nazwą organizacji. Organizacja nie została usunięta."
+      remove: "Usuń organizację"
+
+    dialog_actions:
+      cancel: "Anuluj"
+
+  account_setups:
+    flash:
+      done: "Pomyślnie skonfigurowano konto."
+    edit:
+      page_title: "Konfiguracja konta"
+      title: "Uzupełnij swoje dane"
+      lead: "To jednorazowy krok. Imię i nazwisko zobaczą prowadzący w Twoich grupach."
+      email: "Adres e-mail"
+      full_name: "Imię i nazwisko"
+      full_name_placeholder: "Jan Nowak"
+      submit: "Zapisz i przejdź dalej"
+      logout: "Wyloguj"
+
+  activerecord:
+    errors:
+      models:
+        organization:
+          attributes:
+            max_members:
+              below_members: "Limit nie może być mniejszy niż obecna liczba członków (%{count})."
+          usos_undeletable: "Organizacji powiązanej z USOS nie można usunąć."
+        user:
+          attributes:
+            organization:
+              member_limit: "Organizacja osiągnęła limit członków."
diff --git a/config/locales/views/passwordless_mailer.en.yml b/config/locales/views/passwordless_mailer.en.yml
new file mode 100644
index 00000000..065c952d
--- /dev/null
+++ b/config/locales/views/passwordless_mailer.en.yml
@@ -0,0 +1,12 @@
+en:
+  passwordless_mailer:
+    token_email:
+      subject: "Logging in to Gamification Hub"
+      title: "Log in"
+      greeting: "Hi, %{name}!"
+      body: "Click the button below to log in. No password needed."
+      text_body: "To log in, open the link below. No password needed."
+      button: "Log in"
+      valid_for: "The link is valid for %{minutes}."
+      fallback: "The link is valid for %{minutes}. If the button doesn't work, copy this address into your browser:"
+      ignore: "If it wasn't you trying to log in, you can ignore this message."
diff --git a/config/locales/views/passwordless_mailer.pl.yml b/config/locales/views/passwordless_mailer.pl.yml
new file mode 100644
index 00000000..05f04bd1
--- /dev/null
+++ b/config/locales/views/passwordless_mailer.pl.yml
@@ -0,0 +1,12 @@
+pl:
+  passwordless_mailer:
+    token_email:
+      subject: "Logowanie do systemu Gamification Hub"
+      title: "Zaloguj się"
+      greeting: "Cześć, %{name}!"
+      body: "Kliknij przycisk poniżej, aby zalogować się. Hasło nie jest potrzebne."
+      text_body: "Aby zalogować się, otwórz poniższy link. Hasło nie jest potrzebne."
+      button: "Zaloguj się"
+      valid_for: "Link jest ważny przez %{minutes}."
+      fallback: "Link jest ważny przez %{minutes}. Jeśli przycisk nie działa, skopiuj ten adres do przeglądarki:"
+      ignore: "Jeśli to nie Ty próbowałeś się zalogować, możesz zignorować tę wiadomość."
diff --git a/config/locales/views/ranking.en.yml b/config/locales/views/ranking.en.yml
new file mode 100644
index 00000000..458d706b
--- /dev/null
+++ b/config/locales/views/ranking.en.yml
@@ -0,0 +1,73 @@
+en:
+  ranking:
+    flash:
+      hidden: "The ranking is hidden from students."
+      full: "The full ranking is visible."
+      podium: "The ranking is visible: podium and own place."
+
+    show:
+      page_title: "Ranking - %{group}"
+
+    confirm_mode:
+      page_title: "Ranking - %{mode}"
+      full_title: "Show the full ranking?"
+      full_body: "Every student will see everyone's places and nicknames, including those at the bottom of the list."
+      podium_title: "Limit the ranking to the podium?"
+      podium_body: "Students will keep the top 3 places and their own. Nobody will see who is at the bottom of the list."
+      keep_podium: "Keep the podium"
+      show_full: "Show the full ranking"
+      show_podium: "Show only the podium"
+
+    confirm_visibility:
+      show_page_title: "Show ranking"
+      hide_page_title: "Hide ranking"
+      show_title: "Show the ranking to students?"
+      show_body: "Students will see the ranking right away. Choose how much they see."
+      modes_label: "What students see"
+      podium_body: "Everyone sees the top 3 places. Each student also sees their own place, but not anyone else's."
+      full_body: "Everyone sees everyone's places and nicknames, including at the bottom of the list."
+      show: "Show ranking"
+      hide_title: "Hide the ranking from students?"
+      hide_body: "Students will stop seeing places and nicknames. You still see the whole ranking, and collected currency and ranks don't change."
+      keep_visible: "Keep it visible"
+      hide: "Hide ranking"
+
+    board:
+      table_label: "Ranking"
+      place: "Place"
+      nickname_and_student: "Nickname and student"
+      nickname: "Nickname"
+      rank: "Rank"
+      collected: "Collected"
+      hidden_rows: "The other places are hidden"
+      place_label: "Place %{place}"
+      you: "You"
+      no_nickname: "No nickname"
+
+    teacher_board:
+      title: "Ranking"
+      lead: "Ordered by total currency collected (%{currency}). Students only see nicknames; you also see full names."
+      visible: "Visible to students"
+      modes_label: "What students see"
+      hidden_note: "The ranking is hidden from students."
+      hidden_note_tail: "You can still see it."
+      podium_note: "Students only see the podium and their own place."
+      podium_note_tail: "Nobody will see who is at the bottom of the list. You see everyone."
+      footnote: "A tie gives the same place. Students without a nickname are shown by their full name."
+      empty_title: "Nobody has joined the group yet"
+      empty_body: "The ranking will build itself once students join and start collecting currency."
+      invites: "Invites"
+
+    student_board:
+      title: "Ranking"
+      hidden_lead: "The teacher has hidden the ranking for now."
+      podium_lead: "The teacher only shows the podium. Only you can see your own place."
+      full_lead: "Ordered by total currency collected (%{currency})."
+      own_place: "#%{place}"
+      own_place_label: "Your place out of %{count}"
+      collected: "Collected in total"
+      nickname: "Your nickname in this group:"
+      no_nickname: "none"
+      change: "Change"
+      hidden_title: "The ranking is hidden right now"
+      hidden_body: "Keep collecting currency. Once the teacher turns the ranking on, you'll see your place here."
diff --git a/config/locales/views/ranking.pl.yml b/config/locales/views/ranking.pl.yml
new file mode 100644
index 00000000..026efa95
--- /dev/null
+++ b/config/locales/views/ranking.pl.yml
@@ -0,0 +1,73 @@
+pl:
+  ranking:
+    flash:
+      hidden: "Ranking ukryty przed studentami."
+      full: "Ranking widoczny w całości."
+      podium: "Ranking widoczny: podium i własne miejsce."
+
+    show:
+      page_title: "Ranking - %{group}"
+
+    confirm_mode:
+      page_title: "Ranking - %{mode}"
+      full_title: "Pokazać pełny ranking?"
+      full_body: "Każdy student zobaczy miejsca i pseudonimy wszystkich, także osób na końcu listy."
+      podium_title: "Ograniczyć ranking do podium?"
+      podium_body: "Studentom zostaną pierwsze 3 miejsca i ich własne. Nikt nie zobaczy, kto jest na końcu listy."
+      keep_podium: "Zostaw podium"
+      show_full: "Pokaż pełny ranking"
+      show_podium: "Pokaż tylko podium"
+
+    confirm_visibility:
+      show_page_title: "Pokaż ranking"
+      hide_page_title: "Ukryj ranking"
+      show_title: "Pokazać ranking studentom?"
+      show_body: "Studenci zobaczą ranking od razu. Wybierz, ile mają widzieć."
+      modes_label: "Co widzą studenci"
+      podium_body: "Wszyscy widzą pierwsze 3 miejsca. Każdy widzi też swoje miejsce, ale nie cudze."
+      full_body: "Wszyscy widzą miejsca i pseudonimy wszystkich, także na końcu listy."
+      show: "Pokaż ranking"
+      hide_title: "Ukryć ranking przed studentami?"
+      hide_body: "Studenci przestaną widzieć miejsca i pseudonimy. Ty nadal widzisz cały ranking, a zebrana waluta i rangi nie zmieniają się."
+      keep_visible: "Zostaw widoczny"
+      hide: "Ukryj ranking"
+
+    board:
+      table_label: "Ranking"
+      place: "Miejsce"
+      nickname_and_student: "Pseudonim i student"
+      nickname: "Pseudonim"
+      rank: "Ranga"
+      collected: "Zebrane"
+      hidden_rows: "Pozostałe miejsca są ukryte"
+      place_label: "Miejsce %{place}"
+      you: "Ty"
+      no_nickname: "Bez pseudonimu"
+
+    teacher_board:
+      title: "Ranking"
+      lead: "Kolejność według łącznie zebranej waluty (%{currency}). Studenci widzą tylko pseudonimy, Ty widzisz też imiona i nazwiska."
+      visible: "Widoczny dla studentów"
+      modes_label: "Co widzą studenci"
+      hidden_note: "Ranking jest ukryty przed studentami."
+      hidden_note_tail: "Ty nadal go widzisz."
+      podium_note: "Studenci widzą tylko podium i swoje miejsce."
+      podium_note_tail: "Nikt nie zobaczy, kto jest na końcu listy. Ty widzisz wszystkich."
+      footnote: "Remis daje to samo miejsce. Studenci bez pseudonimu są widoczni pod imieniem i nazwiskiem."
+      empty_title: "Nikt jeszcze nie dołączył do grupy"
+      empty_body: "Ranking ułoży się sam, gdy studenci dołączą i zaczną zbierać walutę."
+      invites: "Zaproszenia"
+
+    student_board:
+      title: "Ranking"
+      hidden_lead: "Prowadzący ukrył ranking na razie."
+      podium_lead: "Prowadzący pokazuje tylko podium. Swoje miejsce widzisz tylko Ty."
+      full_lead: "Kolejność według łącznie zebranej waluty (%{currency})."
+      own_place: "%{place}."
+      own_place_label: "Twoje miejsce z %{count}"
+      collected: "Zebrane łącznie"
+      nickname: "Twój pseudonim w tej grupie:"
+      no_nickname: "brak"
+      change: "Zmień"
+      hidden_title: "Ranking jest teraz ukryty"
+      hidden_body: "Zbieraj dalej walutę. Gdy prowadzący włączy ranking, zobaczysz tu swoje miejsce."
diff --git a/config/locales/views/ranks.en.yml b/config/locales/views/ranks.en.yml
new file mode 100644
index 00000000..33c28c8c
--- /dev/null
+++ b/config/locales/views/ranks.en.yml
@@ -0,0 +1,125 @@
+en:
+  ranks:
+    flash:
+      created: "Added the “%{name}” rank."
+      updated: "Saved the “%{name}” rank."
+      destroyed: "Deleted the “%{name}” rank."
+      blocked: "Can't delete the “%{name}” rank: the items %{items} require it."
+
+    # RanksHelper; rank_form_controller.ts gets the same keys through the form.
+    helpers:
+      starting: "Starting rank"
+      starting_sentence: "Starting rank."
+      from: "From %{min} collected"
+      from_sentence: "From %{min} collected."
+      summary_no_discount: "%{opening}, no discount"
+      summary_discount: "%{opening}, −%{discount}% in the shop"
+      gives_discount: "Gives −%{discount}% in the shop."
+      discount: "−%{discount}% in the shop"
+      no_discount: "No discount"
+      required: "Required: %{min} collected."
+      name_placeholder: "Rank name"
+      new_rank: "New rank"
+      from_short: "from %{min}"
+
+    index:
+      title: "Ranks"
+
+    new:
+      page_title: "New rank"
+
+    edit:
+      page_title: "Edit rank - %{name}"
+
+    teacher_ladder:
+      title: "Ranks"
+      lead:
+        one: "%{count} rank. A rank depends on the total currency collected, so spending it doesn't lower the rank."
+        other: "%{count} ranks. A rank depends on the total currency collected, so spending it doesn't lower the rank."
+      new: "New rank"
+      gap: "↑ %{count} collected to promote"
+      required_by: "Required to buy: %{items}"
+      holders:
+        one: "student"
+        other: "students"
+      progress_label: "Students with the %{name} rank"
+      empty_title: "There are no ranks yet"
+      empty_body: "Add ranks so students can see what they are working towards. A rank depends on the total currency collected, and each can give a discount in the shop."
+
+    student_ladder:
+      title: "Ranks"
+      lead: "Your rank grows with the total currency you collect. Spending it doesn't lower your rank."
+      yours: "Your rank"
+      achieved: "Earned"
+      to_first: "%{collected} of %{needed} to the first rank"
+      to_next: "%{collected} of %{needed} to the next one"
+      progress_label: "Progress to the rank above %{name}"
+      top: "Highest rank"
+      missing: "%{count} to go"
+      empty_title: "This group has no ranks yet"
+      empty_body: "The teacher hasn't added any. Keep collecting currency — once ranks appear, everything you've collected so far will count."
+
+    preview:
+      summary: "Rank preview"
+      card: "Rank card"
+      ladder: "Rank ladder"
+      this_rank: "(this rank)"
+
+    form:
+      breadcrumb: "Ranks"
+      new_title: "New rank"
+      edit_title: "Edit rank"
+      lead: "The preview shows where the rank lands on the ladder and how many students it covers."
+      holders:
+        one: "%{count} student has this rank."
+        other: "%{count} students have this rank."
+      holders_note: "Changing the threshold may move students up or down. The preview shows the effect."
+      card: "Rank card"
+      card_hint: "This is how the rank looks on the group page and in the ranking."
+      name_placeholder: "e.g. Fleet Admiral"
+      threshold_section: "Threshold and reward"
+      threshold_hint: "A rank depends on the total currency collected, so spending it doesn't lower the rank."
+      threshold: "Collected required"
+      discount: "Shop discount"
+      removal_hint: "Students with this rank will drop to the rank below. Items that require it must first be assigned to another rank."
+      remove: "Delete rank"
+      create: "Add rank"
+      # rank_form_controller.ts
+      js:
+        impact_got_lead: "Right away it goes to "
+        impact_got:
+          one: "%{count} student"
+          other: "%{count} students"
+        impact_got_tail: ". Everyone else will see it as their next goal."
+        impact_nobody: "Nobody has collected that much yet. Students will see it as their next goal."
+        impact_unchanged: "No student will change rank."
+        impact_changed_lead: "After saving, "
+        impact_changed:
+          one: "%{count} student will change rank"
+          other: "%{count} students will change rank"
+        impact_up: "%{count} promoted"
+        impact_down: "%{count} demoted"
+        warn_below: "The rank below (%{name}) gives −%{other}%, but this one only −%{discount}%. A promotion would lower the discount."
+        warn_above: "The rank above (%{name}) only gives −%{other}%. A promotion to it would lower the discount."
+
+    confirm_destroy:
+      page_title: "Delete rank %{name}"
+      title: "Delete the “%{name}” rank?"
+      body: "Students with this rank will drop to the rank below."
+      blocked:
+        one: "The item %{items} requires this rank. Before deleting it, assign that item another rank."
+        other: "The items %{items} require this rank. Before deleting it, assign those items another rank."
+      remove: "Delete rank"
+
+  activerecord:
+    errors:
+      models:
+        rank:
+          attributes:
+            name:
+              blank: "Enter the rank name."
+            discount:
+              out_of_range: "The discount must be between 0 and 100%."
+            required_currency_value:
+              negative: "The threshold can't be negative."
+              threshold_taken: "The %{rank} rank already has the threshold %{threshold}. Choose another one."
diff --git a/config/locales/views/ranks.pl.yml b/config/locales/views/ranks.pl.yml
new file mode 100644
index 00000000..bd561b7d
--- /dev/null
+++ b/config/locales/views/ranks.pl.yml
@@ -0,0 +1,135 @@
+pl:
+  ranks:
+    flash:
+      created: "Dodano rangę „%{name}”."
+      updated: "Zapisano rangę „%{name}”."
+      destroyed: "Usunięto rangę „%{name}”."
+      blocked: "Nie można usunąć rangi „%{name}”: wymagają jej przedmioty %{items}."
+
+    # RanksHelper; rank_form_controller.ts gets the same keys through the form.
+    helpers:
+      starting: "Ranga startowa"
+      starting_sentence: "Ranga startowa."
+      from: "Od %{min} zebranych"
+      from_sentence: "Od %{min} zebranych."
+      summary_no_discount: "%{opening}, bez zniżki"
+      summary_discount: "%{opening}, −%{discount}% w sklepie"
+      gives_discount: "Daje −%{discount}% w sklepie."
+      discount: "−%{discount}% w sklepie"
+      no_discount: "Bez zniżki"
+      required: "Wymagane: %{min} zebranych."
+      name_placeholder: "Nazwa rangi"
+      new_rank: "Nowa ranga"
+      from_short: "od %{min}"
+
+    index:
+      title: "Rangi"
+
+    new:
+      page_title: "Nowa ranga"
+
+    edit:
+      page_title: "Edytuj rangę - %{name}"
+
+    teacher_ladder:
+      title: "Rangi"
+      lead:
+        one: "%{count} ranga. Ranga zależy od łącznie zebranej waluty, więc wydawanie jej nie obniża rangi."
+        few: "%{count} rangi. Ranga zależy od łącznie zebranej waluty, więc wydawanie jej nie obniża rangi."
+        many: "%{count} rang. Ranga zależy od łącznie zebranej waluty, więc wydawanie jej nie obniża rangi."
+        other: "%{count} rangi. Ranga zależy od łącznie zebranej waluty, więc wydawanie jej nie obniża rangi."
+      new: "Nowa ranga"
+      gap: "↑ %{count} zebranych do awansu"
+      required_by: "Wymagana do zakupu: %{items}"
+      holders:
+        one: "student"
+        few: "studentów"
+        many: "studentów"
+        other: "studenta"
+      progress_label: "Studenci z rangą %{name}"
+      empty_title: "Nie ma jeszcze żadnych rang"
+      empty_body: "Dodaj rangi, żeby studenci widzieli, do czego dążą. Ranga zależy od łącznie zebranej waluty, a każda może dawać zniżkę w sklepie."
+
+    student_ladder:
+      title: "Rangi"
+      lead: "Ranga rośnie razem z łącznie zebraną walutą. Wydawanie jej nie obniża rangi."
+      yours: "Twoja ranga"
+      achieved: "Zdobyta"
+      to_first: "%{collected} z %{needed} do pierwszej rangi"
+      to_next: "%{collected} z %{needed} do następnej"
+      progress_label: "Postęp do rangi wyżej niż %{name}"
+      top: "Najwyższa ranga"
+      missing: "Brakuje %{count}"
+      empty_title: "W tej grupie nie ma jeszcze rang"
+      empty_body: "Prowadzący ich nie dodał. Zbieraj walutę — kiedy rangi się pojawią, zaliczy się wszystko, co zebrałeś do tej pory."
+
+    preview:
+      summary: "Podgląd rangi"
+      card: "Karta rangi"
+      ladder: "Drabinka rang"
+      this_rank: "(ta ranga)"
+
+    form:
+      breadcrumb: "Rangi"
+      new_title: "Nowa ranga"
+      edit_title: "Edytuj rangę"
+      lead: "Podgląd obok pokazuje, gdzie ranga trafi na drabince i ilu studentów obejmie."
+      holders:
+        one: "%{count} student ma tę rangę."
+        few: "%{count} studentów ma tę rangę."
+        many: "%{count} studentów ma tę rangę."
+        other: "%{count} studenta ma tę rangę."
+      holders_note: "Zmiana progu może przesunąć studentów w górę lub w dół. Podgląd obok pokazuje skutki."
+      card: "Karta rangi"
+      card_hint: "Tak ranga wygląda na stronie grupy i w rankingu."
+      name_placeholder: "np. Admirał Floty"
+      threshold_section: "Próg i nagroda"
+      threshold_hint: "Ranga zależy od łącznie zebranej waluty, więc wydawanie jej nie obniża rangi."
+      threshold: "Wymagane zebrane"
+      discount: "Zniżka w sklepie"
+      removal_hint: "Studenci z tą rangą spadną do rangi niżej. Przedmioty, które jej wymagają, trzeba będzie najpierw przypisać do innej rangi."
+      remove: "Usuń rangę"
+      create: "Dodaj rangę"
+      # rank_form_controller.ts
+      js:
+        impact_got_lead: "Od razu dostanie ją "
+        impact_got:
+          one: "%{count} student"
+          few: "%{count} studentów"
+          many: "%{count} studentów"
+          other: "%{count} studenta"
+        impact_got_tail: ". Pozostali zobaczą ją jako kolejny cel."
+        impact_nobody: "Na razie nikt nie ma tylu zebranych. Studenci zobaczą ją jako kolejny cel."
+        impact_unchanged: "Żaden student nie zmieni rangi."
+        impact_changed_lead: "Po zapisaniu "
+        impact_changed:
+          one: "%{count} student zmieni rangę"
+          few: "%{count} studentów zmieni rangę"
+          many: "%{count} studentów zmieni rangę"
+          other: "%{count} studenta zmieni rangę"
+        impact_up: "%{count} awansuje"
+        impact_down: "%{count} spadnie"
+        warn_below: "Ranga niżej (%{name}) daje −%{other}%, a ta tylko −%{discount}%. Awans obniżyłby zniżkę."
+        warn_above: "Ranga wyżej (%{name}) daje tylko −%{other}%. Awans na nią obniżyłby zniżkę."
+
+    confirm_destroy:
+      page_title: "Usuń rangę %{name}"
+      title: "Usunąć rangę „%{name}”?"
+      body: "Studenci z tą rangą spadną do rangi niżej."
+      blocked:
+        one: "Przedmiot %{items} wymaga tej rangi. Zanim ją usuniesz, przypisz mu inną rangę."
+        other: "Przedmioty %{items} wymagają tej rangi. Zanim ją usuniesz, przypisz im inną rangę."
+      remove: "Usuń rangę"
+
+  activerecord:
+    errors:
+      models:
+        rank:
+          attributes:
+            name:
+              blank: "Podaj nazwę rangi."
+            discount:
+              out_of_range: "Zniżka musi mieścić się między 0 a 100%."
+            required_currency_value:
+              negative: "Próg nie może być ujemny."
+              threshold_taken: "Ranga %{rank} ma już próg %{threshold}. Wybierz inny."
diff --git a/config/locales/views/sessions.en.yml b/config/locales/views/sessions.en.yml
new file mode 100644
index 00000000..7c5793c1
--- /dev/null
+++ b/config/locales/views/sessions.en.yml
@@ -0,0 +1,10 @@
+en:
+  sessions:
+    new:
+      title: "Log in"
+      lead: "Choose the way you use at your university or school."
+      usos: "Log in with USOS"
+      usos_hint: "University students and teachers"
+      or: "or"
+      email: "Log in with e-mail"
+      email_hint: "School pupils and people added by an administrator"
diff --git a/config/locales/views/sessions.pl.yml b/config/locales/views/sessions.pl.yml
new file mode 100644
index 00000000..a87dce14
--- /dev/null
+++ b/config/locales/views/sessions.pl.yml
@@ -0,0 +1,10 @@
+pl:
+  sessions:
+    new:
+      title: "Zaloguj się"
+      lead: "Wybierz sposób, z którego korzystasz na swojej uczelni lub w szkole."
+      usos: "Zaloguj się przez USOS"
+      usos_hint: "Studenci i nauczyciele uczelni"
+      or: "albo"
+      email: "Zaloguj się e-mailem"
+      email_hint: "Uczniowie szkół i osoby dodane przez administratora"
diff --git a/config/locales/views/shared.en.yml b/config/locales/views/shared.en.yml
new file mode 100644
index 00000000..1325562b
--- /dev/null
+++ b/config/locales/views/shared.en.yml
@@ -0,0 +1,108 @@
+en:
+  shared:
+    # Generic buttons and labels used across screens.
+    actions:
+      add: "Add"
+      back_to_editing: "Back to editing"
+      cancel: "Cancel"
+      close: "Close"
+      edit: "Edit"
+      fewer: "Fewer"
+      more: "More"
+      name: "Name"
+      next: "Next"
+      optional: "(optional)"
+      preview: "Preview"
+      removal: "Deleting"
+      remove: "Remove"
+      save: "Save"
+      save_changes: "Save changes"
+    # shared/_sheet_form — template (new, edit) and sheet settings.
+    sheet_form:
+      template_new_title: "New sheet template"
+      template_edit_title: "Edit sheet template"
+      sheet_title: "Sheet settings"
+      breadcrumb: "Grade sheets"
+      new_template: "New template"
+      sheet_lead: "Changes only apply to this sheet."
+      template_lead: "The preview shows the grade sheet header."
+      template_changes: "Changes only apply to sheets created from now on."
+      sheets_range_unchanged: "%{first} – %{last} stay unchanged."
+      sheet_unchanged: "%{name} stays unchanged."
+      awarded:
+        one: "%{count} reward has already been awarded in this sheet."
+        other: "%{count} rewards have already been awarded in this sheet."
+      awarded_note: "Column changes only apply to future rewards. The template %{name} doesn't change."
+      sheet_name: "Sheet name"
+      template_name: "Template name"
+      sheet_name_placeholder: "e.g. Lab 5 (14.10)"
+      template_name_placeholder: "e.g. Lab"
+      name_example: "Lab"
+      template_name_hint: "New sheets get the template name with the next number, e.g. %{example} 6."
+      sheet_columns: "Grade sheet columns"
+      template_categories: "Reward categories"
+      columns_hint: "Each category is a column in the grade sheet. The order here is the column order."
+      add_column: "Add column"
+      add_category: "Add category"
+      summary: "%{count} in the grade sheet. A student can earn up to %{max} %{currency} per sheet."
+      sheet_removal_hint: "The sheet will disappear from the list, and awarded rewards stay with the students and in their history."
+      template_removal_hint: "The template will disappear from the list, and sheets created from it stay."
+      remove_sheet: "Delete sheet"
+      remove_template: "Delete template"
+      no_changes: "No changes"
+      create: "Create template"
+      discard_title: "Discard changes?"
+      discard_body: "Unsaved changes will be lost."
+      discard: "Discard changes"
+      sample_names: ["Alex Johnson", "Barbara Miller"]
+      # sheet_form_controller.ts
+      js:
+        columns:
+          one: "%{count} column"
+          other: "%{count} columns"
+        dirty: "Unsaved changes"
+        clean: "No changes"
+        name_label: "Category %{number}: for what"
+        reward_label: "Reward for category %{number}"
+        story_label: "Story description of category %{number}"
+        destroy_column: "Remove column %{number}"
+        destroy_category: "Remove category %{number}"
+
+    category_row:
+      drag: "Drag to reorder"
+      name_placeholder: "For what, e.g. Helping others"
+      add_story: "Add a story description"
+      story_placeholder: "Story description, e.g. Towing a damaged ship"
+      sheet_only: "Only in this sheet"
+      hidden_column: "Hidden in the grade sheet"
+      awarded:
+        one: "%{count} reward awarded."
+        other: "%{count} rewards awarded."
+      locked_note: "The column can't be removed, but it can be hidden."
+      reward_note: "The new value only applies to future rewards."
+      move_up: "Move up"
+      move_down: "Move down"
+      show: "Show in the grade sheet"
+      hide: "Hide in the grade sheet"
+
+    grid_preview:
+      summary: "Grade sheet preview"
+      header: "Grade sheet header"
+      student: "Student"
+      hint: "Hover over a header in the real sheet to see the story description."
+
+    # shared/_image_field — the defaults, overridden per form.
+    image_field:
+      label: "Image"
+      presets: "Ready-made images"
+      own: "Your image"
+      upload: "Or upload your own image"
+      hint: "JPG or PNG, ideally at least 400 px."
+      crop: "Crop the image"
+      cropped: "Move and resize the selection — the preview updates as you go. We save a card-shaped crop, so it fills the card completely. In lists you'll see it as a square thumbnail, also in full."
+      preset_label: "%{label}: %{name}"
+      choose_file: "Choose file"
+
+    register_prompt:
+      no_account: "Don't have an account?"
+      register: "Sign up"
diff --git a/config/locales/views/shared.pl.yml b/config/locales/views/shared.pl.yml
new file mode 100644
index 00000000..f7668f8d
--- /dev/null
+++ b/config/locales/views/shared.pl.yml
@@ -0,0 +1,114 @@
+pl:
+  shared:
+    # Generic buttons and labels used across screens.
+    actions:
+      add: "Dodaj"
+      back_to_editing: "Wróć do edycji"
+      cancel: "Anuluj"
+      close: "Zamknij"
+      edit: "Edytuj"
+      fewer: "Mniej"
+      more: "Więcej"
+      name: "Nazwa"
+      next: "Dalej"
+      optional: "(opcjonalnie)"
+      preview: "Podgląd"
+      removal: "Usuwanie"
+      remove: "Usuń"
+      save: "Zapisz"
+      save_changes: "Zapisz zmiany"
+    # shared/_sheet_form — template (new, edit) and sheet settings.
+    sheet_form:
+      template_new_title: "Nowy szablon arkusza"
+      template_edit_title: "Edytuj szablon arkusza"
+      sheet_title: "Ustawienia arkusza"
+      breadcrumb: "Arkusze ocen"
+      new_template: "Nowy szablon"
+      sheet_lead: "Zmiany dotyczą tylko tego arkusza."
+      template_lead: "Podgląd obok pokazuje nagłówek tabeli ocen."
+      template_changes: "Zmiany dotyczą tylko arkuszy utworzonych od teraz."
+      sheets_range_unchanged: "%{first} – %{last} zostają bez zmian."
+      sheet_unchanged: "%{name} zostaje bez zmian."
+      awarded:
+        one: "W tym arkuszu przyznano już %{count} nagrodę."
+        few: "W tym arkuszu przyznano już %{count} nagrody."
+        many: "W tym arkuszu przyznano już %{count} nagród."
+        other: "W tym arkuszu przyznano już %{count} nagrody."
+      awarded_note: "Zmiany kolumn dotyczą tylko przyszłych nagród. Szablon %{name} się nie zmienia."
+      sheet_name: "Nazwa arkusza"
+      template_name: "Nazwa szablonu"
+      sheet_name_placeholder: "np. Laboratoria 5 (14.10)"
+      template_name_placeholder: "np. Laboratoria"
+      name_example: "Laboratoria"
+      template_name_hint: "Nowe arkusze dostaną nazwę szablonu z kolejnym numerem, np. %{example} 6."
+      sheet_columns: "Kolumny w tabeli ocen"
+      template_categories: "Kategorie nagród"
+      columns_hint: "Każda kategoria to kolumna w tabeli ocen. Kolejność tutaj to kolejność kolumn."
+      add_column: "Dodaj kolumnę"
+      add_category: "Dodaj kategorię"
+      summary: "%{count} w tabeli ocen. Student może zdobyć do %{max} %{currency} za arkusz."
+      sheet_removal_hint: "Arkusz zniknie z listy, a przyznane nagrody zostają u studentów i w ich historii."
+      template_removal_hint: "Szablon zniknie z listy, a utworzone z niego arkusze zostają."
+      remove_sheet: "Usuń arkusz"
+      remove_template: "Usuń szablon"
+      no_changes: "Brak zmian"
+      create: "Utwórz szablon"
+      discard_title: "Odrzucić zmiany?"
+      discard_body: "Niezapisane zmiany zostaną utracone."
+      discard: "Odrzuć zmiany"
+      sample_names: ["Adam Pawłowski", "Barbara Kowalewska"]
+      # sheet_form_controller.ts
+      js:
+        columns:
+          one: "%{count} kolumna"
+          few: "%{count} kolumny"
+          many: "%{count} kolumn"
+          other: "%{count} kolumny"
+        dirty: "Niezapisane zmiany"
+        clean: "Brak zmian"
+        name_label: "Kategoria %{number}: za co"
+        reward_label: "Nagroda za kategorię %{number}"
+        story_label: "Opis fabularny kategorii %{number}"
+        destroy_column: "Usuń kolumnę %{number}"
+        destroy_category: "Usuń kategorię %{number}"
+
+    category_row:
+      drag: "Przeciągnij, aby zmienić kolejność"
+      name_placeholder: "Za co, np. Pomoc innym"
+      add_story: "Dodaj opis fabularny"
+      story_placeholder: "Opis fabularny, np. Holowanie uszkodzonego statku"
+      sheet_only: "Tylko w tym arkuszu"
+      hidden_column: "Ukryta w tabeli ocen"
+      awarded:
+        one: "Przyznano %{count} nagrodę."
+        few: "Przyznano %{count} nagrody."
+        many: "Przyznano %{count} nagród."
+        other: "Przyznano %{count} nagrody."
+      locked_note: "Kolumny nie można usunąć, można ją ukryć."
+      reward_note: "Nowa wartość obejmie tylko przyszłe nagrody."
+      move_up: "Przesuń wyżej"
+      move_down: "Przesuń niżej"
+      show: "Pokaż w tabeli ocen"
+      hide: "Ukryj w tabeli ocen"
+
+    grid_preview:
+      summary: "Podgląd tabeli ocen"
+      header: "Nagłówek tabeli ocen"
+      student: "Student"
+      hint: "Najedź na nagłówek w prawdziwej tabeli, żeby zobaczyć opis fabularny."
+
+    # shared/_image_field — the defaults, overridden per form.
+    image_field:
+      label: "Grafika"
+      presets: "Gotowe grafiki"
+      own: "Twoja grafika"
+      upload: "Albo wgraj własną grafikę"
+      hint: "JPG lub PNG, najlepiej co najmniej 400 px."
+      crop: "Przytnij grafikę"
+      cropped: "Przesuń i przeskaluj zaznaczenie — podgląd obok zmienia się na bieżąco. Zapisujemy kadr w kształcie karty, więc wypełni ją w całości. Na listach zobaczysz go w kwadratowej miniaturze, też w całości."
+      preset_label: "%{label}: %{name}"
+      choose_file: "Wybierz plik"
+
+    register_prompt:
+      no_account: "Nie masz konta?"
+      register: "Zarejestruj się"
diff --git a/config/locales/views/shop.en.yml b/config/locales/views/shop.en.yml
new file mode 100644
index 00000000..3a0d2ce6
--- /dev/null
+++ b/config/locales/views/shop.en.yml
@@ -0,0 +1,45 @@
+en:
+  shop:
+    flash:
+      unavailable: "You can't buy “%{name}” right now."
+      bought: "Bought: “%{name}”. You have %{balance} left."
+
+    # Shop::ZONES
+    zones:
+      afford: "You can afford now"
+      save: "Saving up for"
+      sealed: "Sealed"
+
+    # PurchaseEligibilityService and ItemPurchaseService.
+    errors:
+      no_lives: "You need at least one life."
+      rank_required: "Required rank: %{rank}."
+      badges_missing: "Missing badges: %{badges}."
+      not_enough: "You don't have enough currency to buy this item."
+      failed: "Something went wrong with the purchase: %{message}"
+
+    helpers:
+      balance_html: "You have %{balance} to spend."
+      discount_badges_html:
+        one: "Your %{badges} badge lowers the price of some items."
+        other: "Your badges %{badges} lower the price of some items."
+
+    index:
+      title: "Shop"
+      to_spend: "to spend"
+      collected: "collected in total"
+      empty_title: "The shop is still empty"
+      empty_body: "The teacher hasn't added any items yet. Keep collecting currency — it will come in handy once the shop opens."
+
+    buy_button:
+      label: "Buy %{name} for %{price}"
+      buy: "Buy for %{price}"
+
+    confirm_buy:
+      page_title: "Buy %{name}"
+      title: "Buy “%{name}”?"
+      price: "Price"
+      left: "You'll have left"
+      discount: "Discount %{label}."
+      notice: "The teacher will be notified about the purchase."
+      buy: "Buy for %{price}"
diff --git a/config/locales/views/shop.pl.yml b/config/locales/views/shop.pl.yml
new file mode 100644
index 00000000..96b3933d
--- /dev/null
+++ b/config/locales/views/shop.pl.yml
@@ -0,0 +1,47 @@
+pl:
+  shop:
+    flash:
+      unavailable: "Nie możesz teraz kupić „%{name}”."
+      bought: "Kupione: „%{name}”. Zostało Ci %{balance}."
+
+    # Shop::ZONES
+    zones:
+      afford: "Stać cię teraz"
+      save: "Zbierasz na to"
+      sealed: "Zapieczętowane"
+
+    # PurchaseEligibilityService and ItemPurchaseService.
+    errors:
+      no_lives: "Wymagane jest posiadanie przynajmniej jednego życia."
+      rank_required: "Wymagana ranga: %{rank}."
+      badges_missing: "Brakujące odznaki: %{badges}."
+      not_enough: "Masz za mało waluty, aby kupić ten przedmiot."
+      failed: "Wystąpił błąd podczas zakupu: %{message}"
+
+    helpers:
+      balance_html: "Masz %{balance} do wydania."
+      discount_badges_html:
+        one: "Twoja odznaka %{badges} obniża ceny niektórych przedmiotów."
+        few: "Twoje odznaki %{badges} obniżają ceny niektórych przedmiotów."
+        many: "Twoje odznaki %{badges} obniżają ceny niektórych przedmiotów."
+        other: "Twoje odznaki %{badges} obniżają ceny niektórych przedmiotów."
+
+    index:
+      title: "Sklep"
+      to_spend: "do wydania"
+      collected: "zebrane łącznie"
+      empty_title: "Sklep jest jeszcze pusty"
+      empty_body: "Prowadzący nie dodał jeszcze przedmiotów. Zbieraj walutę — przyda się, kiedy sklep się otworzy."
+
+    buy_button:
+      label: "Kup %{name} za %{price}"
+      buy: "Kup za %{price}"
+
+    confirm_buy:
+      page_title: "Kup %{name}"
+      title: "Kupić „%{name}”?"
+      price: "Cena"
+      left: "Zostanie Ci"
+      discount: "Zniżka %{label}."
+      notice: "Prowadzący dostanie powiadomienie o zakupie."
+      buy: "Kup za %{price}"
diff --git a/config/locales/views/story_group_invites.en.yml b/config/locales/views/story_group_invites.en.yml
new file mode 100644
index 00000000..fab933b0
--- /dev/null
+++ b/config/locales/views/story_group_invites.en.yml
@@ -0,0 +1,126 @@
+en:
+  story_group_invites:
+    flash:
+      created: "Created the code %{code}. Click “Show” to display it to students."
+      updated: "Saved the invite %{code}."
+      destroyed: "Deleted the invite %{code}."
+
+    # StoryGroupInvite#status_label
+    statuses:
+      active: "Active"
+      expired: "Expired"
+      exhausted: "Used up"
+
+    helpers:
+      uses_unlimited: "%{uses}, no limit"
+      uses_limited: "%{uses} of %{max}"
+      no_expiry: "No expiry date"
+      expires: "Expires %{date}"
+      expired: "Expired %{date}"
+      stat_sentence: "Uses: %{uses}. %{expiry}."
+      code_label: "Code: %{code}"
+      option: "%{code} – %{uses}, %{validity}"
+      option_unlimited: "no limit"
+      option_no_expiry: "no expiry"
+      option_valid_until: "valid until %{date}"
+
+    # InviteForm and invite_form_controller.ts.
+    summary:
+      sentence: "The code will work %{limit} %{expiry}."
+      limit:
+        one: "for %{count} person"
+        other: "for %{count} people"
+      no_limit: "with no limit of people"
+      expiry: "until %{date}"
+      no_expiry: "and with no expiry date"
+      unit:
+        one: "person"
+        other: "people"
+      # %{day} %{month} two digits, %{dayNumber} without padding, %{monthName} short.
+      stamp: "%{monthName} %{dayNumber}, %{time}"
+
+    index:
+      title: "Invites"
+      lead: "The code has 6 characters with no confusable letters (no O, 0, I, 1 or L). Students type it into “Join a group” or scan the QR code."
+      new: "New invite"
+      code: "Code"
+      status: "Status"
+      uses: "Uses"
+      validity: "Validity"
+      empty: "No active invites. Create a new one so students can join."
+      inactive: "Inactive (%{count}): expired and used up"
+
+    invite_row:
+      uses: "Uses: %{uses}"
+      usage_label: "Usage of code %{code}"
+      show: "Show"
+      edit_label: "Edit invite %{code}"
+      remove: "Delete"
+      remove_label: "Delete invite %{code}"
+
+    copy_button:
+      title: "Copy code %{code}"
+      done: "Copied"
+      message: "Copied the code %{code}."
+      label: "Copy code"
+
+
+    code:
+      title: "Join the group %{name}"
+      hint: "Type the code into the app (“Join a group”) or scan the QR code."
+
+    quick:
+      page_title: "Code for students"
+      title: "Join the group %{name}"
+      hint: "Type the code into the app (“Join a group”) or scan the QR code."
+      picker: "Invite (active: %{count}, newest first)"
+      hidden_note: "Expired and used-up invites are hidden. You'll find all of them in the Invites tab."
+      empty: "No active invites. Create a new one so students can join."
+      new: "New invite"
+      manage: "Manage invites"
+
+    show:
+      page_title: "Invite %{code}"
+
+    new:
+      page_title: "New invite"
+
+    edit:
+      page_title: "Edit invite %{code}"
+
+    form:
+      edit_title: "Edit invite %{code}"
+      new_title: "New invite"
+      edit_hint: "The code stays the same. You only change the limits."
+      new_hint: "Both limits are optional."
+      today: "For today's class"
+      no_limits: "No limits"
+      limit: "Use limit"
+      limit_hint: "The code stops working once this many people have joined."
+      expiry: "Expiry date"
+      expiry_hint: "After this moment the code stops working."
+      date: "Date"
+      time: "Time"
+      create: "Create invite"
+
+    confirm_destroy:
+      page_title: "Delete invite %{code}?"
+      title: "Delete invite %{code}?"
+      body: "The code will stop working right away."
+      joined:
+        one: "%{count} person who joined with this code stays in the group."
+        other: "%{count} people who joined with this code stay in the group."
+      remove: "Delete invite"
+
+  activerecord:
+    errors:
+      models:
+        story_group_invite:
+          attributes:
+            max_uses:
+              too_low: "The limit must be at least 1."
+              below_uses:
+                one: "%{count} person has already used this code. The limit can't be lower."
+                other: "%{count} people have already used this code. The limit can't be lower."
+            expires_at:
+              past: "That date has already passed. Choose a later one."
diff --git a/config/locales/views/story_group_invites.pl.yml b/config/locales/views/story_group_invites.pl.yml
new file mode 100644
index 00000000..c1dc3918
--- /dev/null
+++ b/config/locales/views/story_group_invites.pl.yml
@@ -0,0 +1,134 @@
+pl:
+  story_group_invites:
+    flash:
+      created: "Utworzono kod %{code}. Kliknij „Pokaż”, żeby wyświetlić go studentom."
+      updated: "Zapisano zaproszenie %{code}."
+      destroyed: "Usunięto zaproszenie %{code}."
+
+    # StoryGroupInvite#status_label
+    statuses:
+      active: "Aktywne"
+      expired: "Wygasło"
+      exhausted: "Wyczerpane"
+
+    helpers:
+      uses_unlimited: "%{uses}, bez limitu"
+      uses_limited: "%{uses} z %{max}"
+      no_expiry: "Bez daty ważności"
+      expires: "Wygasa %{date}"
+      expired: "Wygasło %{date}"
+      stat_sentence: "Użycia: %{uses}. %{expiry}."
+      code_label: "Kod: %{code}"
+      option: "%{code} – %{uses}, %{validity}"
+      option_unlimited: "bez limitu"
+      option_no_expiry: "bezterminowo"
+      option_valid_until: "ważne do %{date}"
+
+    # InviteForm and invite_form_controller.ts.
+    summary:
+      sentence: "Kod będzie działał %{limit} %{expiry}."
+      limit:
+        one: "dla %{count} osoby"
+        few: "dla %{count} osób"
+        many: "dla %{count} osób"
+        other: "dla %{count} osoby"
+      no_limit: "bez limitu osób"
+      expiry: "do %{date}"
+      no_expiry: "i bez daty ważności"
+      unit:
+        one: "osoba"
+        few: "osoby"
+        many: "osób"
+        other: "osoby"
+      # %{day} %{month} two digits, %{dayNumber} without padding, %{monthName} short.
+      stamp: "%{day}.%{month}, %{time}"
+
+    index:
+      title: "Zaproszenia"
+      lead: "Kod ma 6 znaków bez mylących liter (bez O, 0, I, 1 i L). Studenci wpisują go w „Dołącz do grupy” albo skanują kod QR."
+      new: "Nowe zaproszenie"
+      code: "Kod"
+      status: "Status"
+      uses: "Użycia"
+      validity: "Ważność"
+      empty: "Brak aktywnych zaproszeń. Utwórz nowe, żeby studenci mogli dołączyć."
+      inactive: "Nieaktywne (%{count}): wygasłe i wyczerpane"
+
+    invite_row:
+      uses: "Użycia: %{uses}"
+      usage_label: "Wykorzystanie kodu %{code}"
+      show: "Pokaż"
+      edit_label: "Edytuj zaproszenie %{code}"
+      remove: "Usuń"
+      remove_label: "Usuń zaproszenie %{code}"
+
+    copy_button:
+      title: "Kopiuj kod %{code}"
+      done: "Skopiowano"
+      message: "Skopiowano kod %{code}."
+      label: "Kopiuj kod"
+
+
+    code:
+      title: "Dołącz do grupy %{name}"
+      hint: "Wpisz kod w aplikacji („Dołącz do grupy”) albo zeskanuj kod QR."
+
+    quick:
+      page_title: "Kod dla studentów"
+      title: "Dołącz do grupy %{name}"
+      hint: "Wpisz kod w aplikacji („Dołącz do grupy”) albo zeskanuj kod QR."
+      picker: "Zaproszenie (aktywne: %{count}, najnowsze na górze)"
+      hidden_note: "Wygasłe i wyczerpane zaproszenia są ukryte. Wszystkie znajdziesz w zakładce Zaproszenia."
+      empty: "Brak aktywnych zaproszeń. Utwórz nowe, żeby studenci mogli dołączyć."
+      new: "Nowe zaproszenie"
+      manage: "Zarządzaj zaproszeniami"
+
+    show:
+      page_title: "Zaproszenie %{code}"
+
+    new:
+      page_title: "Nowe zaproszenie"
+
+    edit:
+      page_title: "Edytuj zaproszenie %{code}"
+
+    form:
+      edit_title: "Edytuj zaproszenie %{code}"
+      new_title: "Nowe zaproszenie"
+      edit_hint: "Kod zostaje ten sam. Zmieniasz tylko ograniczenia."
+      new_hint: "Oba ograniczenia są opcjonalne."
+      today: "Na dzisiejsze zajęcia"
+      no_limits: "Bez ograniczeń"
+      limit: "Limit użyć"
+      limit_hint: "Kod przestanie działać, gdy dołączy tyle osób."
+      expiry: "Data ważności"
+      expiry_hint: "Po tej chwili kod przestanie działać."
+      date: "Data"
+      time: "Godzina"
+      create: "Utwórz zaproszenie"
+
+    confirm_destroy:
+      page_title: "Usunąć zaproszenie %{code}?"
+      title: "Usunąć zaproszenie %{code}?"
+      body: "Kod przestanie działać od razu."
+      joined:
+        one: "%{count} osoba, która dołączyła z tym kodem, zostaje w grupie."
+        few: "%{count} osoby, które dołączyły z tym kodem, zostają w grupie."
+        many: "%{count} osób, które dołączyły z tym kodem, zostaje w grupie."
+        other: "%{count} osoby, które dołączyły z tym kodem, zostają w grupie."
+      remove: "Usuń zaproszenie"
+
+  activerecord:
+    errors:
+      models:
+        story_group_invite:
+          attributes:
+            max_uses:
+              too_low: "Limit musi wynosić co najmniej 1."
+              below_uses:
+                one: "Z tego kodu skorzystała już %{count} osoba. Limit nie może być mniejszy."
+                few: "Z tego kodu skorzystały już %{count} osoby. Limit nie może być mniejszy."
+                many: "Z tego kodu skorzystało już %{count} osób. Limit nie może być mniejszy."
+                other: "Z tego kodu skorzystało już %{count} osoby. Limit nie może być mniejszy."
+            expires_at:
+              past: "Ta data już minęła. Wybierz późniejszą."
diff --git a/config/locales/views/story_group_memberships.en.yml b/config/locales/views/story_group_memberships.en.yml
new file mode 100644
index 00000000..816f297c
--- /dev/null
+++ b/config/locales/views/story_group_memberships.en.yml
@@ -0,0 +1,56 @@
+en:
+  story_group_memberships:
+    flash:
+      nickname: "Your nickname in this group: %{name}."
+      left: "You left the group %{name}."
+
+    edit:
+      page_title: "Group settings - %{name}"
+      title: "Group settings"
+      lead: "These settings only apply to the group %{name}."
+      nickname: "Nickname"
+      nickname_hint: "Visible in the ranking only in this group. You can have a different one in other groups."
+      teacher_sees: "What the teacher sees"
+      teacher_sees_hint: "Other students only see your nickname, and only in the ranking."
+      full_name: "Full name"
+      email: "E-mail"
+      university_number: "Student number"
+      none: "None"
+      leave_title: "Leave the group"
+      leave_body: "You'll lose access to the group, and your currency, badges and items in it will be gone. To come back, you'll need a new code from your teacher."
+      leave: "Leave the group"
+
+    nickname:
+      page_title: "Nickname in the group %{name}"
+      title: "Nickname in the group %{name}"
+      hint: "Visible in the ranking only in this group. You can have a different one in other groups. The teacher also sees your full name."
+      save: "Save nickname"
+
+    nickname_field:
+      label: "Your nickname"
+      hint: "Up to 24 characters. Leave it empty to show your full name."
+
+    confirm_leave:
+      page_title: "Leave the group %{name}"
+      title: "Leave the group %{name}?"
+      lose: "You'll lose access to the shop, the ranking and your history in this group: %{balance} %{currency}, %{badges} and %{items}."
+      badges:
+        one: "%{count} badge"
+        other: "%{count} badges"
+      items:
+        one: "%{count} item"
+        other: "%{count} items"
+      warning: "This can't be undone. If you come back to this group with a new code from your teacher, you'll start from scratch."
+      stay: "Stay in the group"
+      leave: "Leave the group"
+
+  # StoryGroupStudent — the nickname is written both when joining and in the
+  # group settings.
+  activerecord:
+    errors:
+      models:
+        story_group_student:
+          attributes:
+            nickname:
+              length: "The nickname must be 2 to 24 characters long."
+              taken: "This nickname is already taken in this group."
diff --git a/config/locales/views/story_group_memberships.pl.yml b/config/locales/views/story_group_memberships.pl.yml
new file mode 100644
index 00000000..f3776c80
--- /dev/null
+++ b/config/locales/views/story_group_memberships.pl.yml
@@ -0,0 +1,60 @@
+pl:
+  story_group_memberships:
+    flash:
+      nickname: "Twój pseudonim w tej grupie: %{name}."
+      left: "Opuszczono grupę %{name}."
+
+    edit:
+      page_title: "Ustawienia w grupie - %{name}"
+      title: "Ustawienia w grupie"
+      lead: "Te ustawienia dotyczą tylko grupy %{name}."
+      nickname: "Pseudonim"
+      nickname_hint: "Widoczny w rankingu tylko w tej grupie. W innych grupach możesz mieć inny."
+      teacher_sees: "Co widzi prowadzący"
+      teacher_sees_hint: "Pozostali studenci widzą tylko Twój pseudonim, i to tylko w rankingu."
+      full_name: "Imię i nazwisko"
+      email: "E-mail"
+      university_number: "Numer indeksu"
+      none: "Brak"
+      leave_title: "Opuść grupę"
+      leave_body: "Stracisz dostęp do grupy, a Twoja waluta, odznaki i przedmioty w niej przepadną. Żeby wrócić, potrzebujesz nowego kodu od prowadzącego."
+      leave: "Opuść grupę"
+
+    nickname:
+      page_title: "Pseudonim w grupie %{name}"
+      title: "Pseudonim w grupie %{name}"
+      hint: "Widoczny w rankingu tylko w tej grupie. W innych grupach możesz mieć inny. Prowadzący widzi też Twoje imię i nazwisko."
+      save: "Zapisz pseudonim"
+
+    nickname_field:
+      label: "Twój pseudonim"
+      hint: "Do 24 znaków. Zostaw puste, żeby pokazywać imię i nazwisko."
+
+    confirm_leave:
+      page_title: "Opuść grupę %{name}"
+      title: "Opuścić grupę %{name}?"
+      lose: "Stracisz dostęp do sklepu, rankingu i swojej historii w tej grupie: %{balance} %{currency}, %{badges} i %{items}."
+      badges:
+        one: "%{count} odznaka"
+        few: "%{count} odznaki"
+        many: "%{count} odznak"
+        other: "%{count} odznaki"
+      items:
+        one: "%{count} przedmiot"
+        few: "%{count} przedmioty"
+        many: "%{count} przedmiotów"
+        other: "%{count} przedmiotu"
+      warning: "Tego nie da się cofnąć. Jeśli wrócisz do tej grupy z nowym kodem od prowadzącego, zaczniesz od zera."
+      stay: "Zostań w grupie"
+      leave: "Opuść grupę"
+
+  # StoryGroupStudent — the nickname is written both when joining and in the
+  # group settings.
+  activerecord:
+    errors:
+      models:
+        story_group_student:
+          attributes:
+            nickname:
+              length: "Pseudonim musi mieć od 2 do 24 znaków."
+              taken: "Ten pseudonim jest już zajęty w tej grupie."
diff --git a/config/locales/views/story_groups.en.yml b/config/locales/views/story_groups.en.yml
new file mode 100644
index 00000000..20a83191
--- /dev/null
+++ b/config/locales/views/story_groups.en.yml
@@ -0,0 +1,425 @@
+en:
+  story_groups:
+    flash:
+      updated: "Saved the group settings."
+      destroyed: "Deleted the group %{name}."
+      duplicate_threshold: "Two ranks can't share a threshold: %{first} and %{second} both have %{value}."
+
+    # StoryGroup.ranking_mode_label / #ranking_summary
+    ranking_modes:
+      podium_and_own: "Podium and own place"
+      full: "Full ranking"
+    ranking_off: "Off"
+
+    # StoryGroupsListing
+    listing:
+      roles:
+        own: "You lead"
+        sup: "You assist"
+        lrn: "You learn"
+      tabs:
+        all: "All"
+        mine: "Mine"
+        teacher: "Teaching"
+        student: "Learning"
+      owner: "Owner: %{name}"
+      no_purchases: "No new purchases"
+      purchases:
+        one: "%{count} new purchase"
+        other: "%{count} new purchases"
+      balance: "You have %{balance} %{currency}"
+
+    # TeacherOverview
+    overview:
+      stats:
+        students: "Students"
+        purchases: "Purchases this week"
+        purchases_note: "for %{amount}"
+        rewards: "Rewards this week"
+        ranking: "Ranking"
+      zero_lives_title: "%{name} has 0 lives"
+      zero_lives_detail: "Can only buy items available at 0 lives."
+      open: "Open"
+      sheet_in_progress: "%{name} in progress"
+      sheet_awarded:
+        one: "Awarded %{count} reward"
+        other: "Awarded %{count} rewards"
+      sheet_pending:
+        one: "%{count} column not graded."
+        other: "%{count} columns not graded."
+      grade: "Grade"
+
+    helpers:
+      teacher_lead:
+        one: "%{count} student in this group. Add a description in the settings to welcome newcomers."
+        other: "%{count} students in this group. Add a description in the settings to welcome newcomers."
+      next_rank: "%{missing} more to the %{rank} rank."
+      next_rank_discount: "That rank gives −%{discount}% in the shop."
+      ranking_off: "The ranking is off — students don't see this podium."
+      ranking_full: "Students see the full ranking, under nicknames."
+      ranking_podium: "Students see the podium and their own place, under nicknames."
+      place: "#%{place} in the group ranking"
+      hand:
+        one: "Grab something in the shop. You can afford %{count} item right now."
+        other: "Grab something in the shop. You can afford %{count} items right now."
+
+    index:
+      title: "Groups"
+      student_lead: "Groups you learn in."
+      teacher_lead: "Groups you lead, assist or learn in."
+      join: "Join a group"
+      create: "Create a group"
+      filter: "Group filter"
+      search: "Search for a group"
+      no_match: "No groups named"
+      no_match_hint: "Clear the search or check the spelling."
+      empty_tab_title: "No groups in this tab"
+      empty_student_title: "You're not in any group yet"
+      empty_title: "You don't have any groups yet"
+      empty_tab_body: "Switch tabs to see the other groups."
+      empty_body: "Got a code from your teacher? Join the group as a participant."
+
+    group_card:
+      students:
+        one: "%{count} student"
+        other: "%{count} students"
+
+    teacher_show:
+      show_code: "Show code to students"
+      create_sheet: "Create a sheet"
+      settings: "Group settings"
+      summary: "Group summary"
+      purchases: "Recent purchases"
+      removed_item: "Item removed from the shop"
+      all_purchases: "All purchases in the group"
+      no_purchases: "Nobody has bought anything yet. Purchases will show up here on their own once students start spending currency in the shop."
+      attention: "Needs attention"
+      recent_sheets: "Recent sheets"
+      open: "Open"
+      no_rewards: "Nobody has rewards from this sheet yet."
+      no_sheets_title: "You don't have any grade sheets yet"
+      no_sheets_body: "A sheet is one class: reward columns and the list of students. Create the first one to start awarding currency."
+
+    student_show:
+      led_by: "Led by %{name}"
+      balance_label: "Your %{currency}"
+      to_spend: "To spend"
+      collected: "Collected in total"
+      lives: "Lives"
+      open_shop: "Open the shop"
+      your_rank: "Your rank"
+      no_rank: "No rank"
+      progress: "%{total} of %{needed}"
+      progress_label: "Progress to the next rank"
+      top_rank: "%{total} collected. This is the highest rank in this group."
+      no_ranks: "The teacher hasn't added ranks yet. The currency you collect still counts — ranks will be assigned on their own once they appear."
+      badges: "Badges"
+      badges_count: "%{earned} of %{total}"
+      items: "Your items"
+      go_to_shop: "Go to the shop"
+      recent: "Recent changes"
+      entry_meta: "%{label}, %{when}"
+      full_history: "Show the full history"
+      no_entries: "Your first entries will show up after class. The teacher awards currency for attendance, punctuality and activity."
+
+    new:
+      page_title: "New group"
+
+    edit:
+      page_title: "Group settings - %{name}"
+
+    created:
+      page_title: "The group %{name} is ready"
+      title: "The group “%{name}” is ready"
+      ranks:
+        one: "%{count} rank"
+        other: "%{count} ranks"
+      badges:
+        one: "%{count} badge"
+        other: "%{count} badges"
+      items:
+        one: "%{count} item"
+        other: "%{count} items"
+      categories:
+        one: "%{count} category in the sheet template"
+        other: "%{count} categories in the sheet template"
+      quick_lead: "Created %{list}."
+      empty_lead: "The group is empty. You'll find the next steps below."
+      invites_note_html: "You'll create a join code in the %{tab} tab when you need it. You can have several codes at once, with a limit of people or an expiry date."
+      invites_tab: "Invites"
+      next: "What's next"
+      quick_steps:
+        - "Invite students: show them the code or the QR code."
+        - "After the first class, create a grade sheet and grade the students."
+        - "Look through the shop and fit the item descriptions to your story."
+      empty_steps:
+        - "Add ranks so students can see what they are working towards."
+        - "Add items to the shop."
+        - "Add badges for special achievements."
+        - "Create a grade sheet template."
+        - "Invite students: show them the code or the QR code."
+      go_to_group: "Go to the group"
+      create_invite: "Create an invite"
+
+    confirm_destroy:
+      page_title: "Delete group %{name}"
+      title: "Delete the group for good?"
+      students:
+        one: "%{count} student"
+        other: "%{count} students"
+      teachers:
+        one: "%{count} teacher"
+        other: "%{count} teachers"
+      lose_access:
+        one: "%{students} and %{teachers} will lose access."
+        other: "%{students} and %{teachers} will lose access."
+      gone: "The history, items and ranking will be gone."
+      confirm: "Type the group name to confirm:"
+      mismatch: "The name you typed doesn't match the group name. The group was not deleted."
+      remove: "Delete group"
+
+    settings:
+      title: "Group settings"
+      lead: "All teachers of this group can change these. Only the owner can delete the group. You set up the ranking in the Ranking tab."
+      group_section: "Group and story"
+      name: "Group name"
+      name_placeholder: "e.g. Space Rabbits"
+      story: "Story"
+      story_hint: "Everyone in the group sees it on the group's home page."
+      art_label: "Group image"
+      art_hint: "JPG or PNG, ideally at least 1200 px wide."
+      currency_section: "Currency"
+      currency_hint: "The new name will show up everywhere, including students' history."
+      currency_name: "Currency name"
+      currency_placeholder: "e.g. Carrots"
+      currency_name_hint: "Use the form that fits after a number — e.g. “Carrots”."
+      lives_section: "Lives"
+      lives: "Starting lives"
+      lives_hint: "Only applies to students who join from now on. You change current students' lives in the student list."
+      back: "Back to the group"
+      delete_title: "Delete group"
+      delete_body: "Deleting takes away everyone's access to the group, its shop, ranking and history. This can't be undone."
+      delete: "Delete group"
+
+    # Shared by the wizard and the settings form (shared/_image_field).
+    currency_icon:
+      label: "Currency icon"
+      presets: "Ready-made icons"
+      own: "Your icon"
+      upload: "Or upload your own icon"
+      hint: "Ideally a PNG with a transparent background, at least 128 px."
+      crop: "Crop the icon"
+      cropped: "Move and resize the selection. We save a square crop, because the icon sits on a round token."
+
+    wizard:
+      steps:
+        - "Group and story"
+        - "Currency and rules"
+        - "How you start"
+        - "Summary"
+      breadcrumb: "Groups"
+      title: "New group"
+      lead: "It takes a few minutes. You can change everything later in the group settings."
+      steps_label: "Steps"
+      name_section: "Name and story"
+      name_hint: "Students will see them in the group list and on the group page."
+      name: "Group name"
+      name_placeholder: "e.g. Order of Algorithms"
+      name_missing: "Enter the group name."
+      story: "Story"
+      story_placeholder: "Once upon a time…"
+      story_hint: "A short story intro. You can change it any time."
+      art_section: "Group image"
+      art_hint: "Shows on the group card, in the side panel and as the group background."
+      currency_section: "Currency name"
+      currency_hint: "It's read after every number, so use the plural form — e.g. “Gold Coins”."
+      currency_name: "Currency name"
+      currency_placeholder: "e.g. Gold Coins"
+      currency_missing: "Enter the currency name."
+      lives_section: "Lives"
+      lives: "Starting lives"
+      fewer_lives: "Fewer lives"
+      more_lives: "More lives"
+      lives_hint: "At 0 lives a student can only buy items marked as available at 0 lives."
+      ranking_section: "Ranking"
+      ranking: "Show the ranking to students"
+      ranking_hint: "Off by default. You can turn it on any time in the Ranking tab."
+      ranking_mode: "What students see"
+      ranking_mode_hint: "“Podium and own place” shows only the top three and the student's own place. “Full ranking” shows the whole list."
+      start_section: "How do you want to start?"
+      start_hint: "Both ways give you a complete group. You can change everything later."
+      start_label: "How to start"
+      recommended: "Recommended for your first group"
+      quick: "Quick start"
+      quick_body: "Ready-made ranks, badges, items and class categories. You'll review and adjust them before the group is created."
+      manual: "From scratch"
+      manual_body: "An empty group. You'll add ranks, badges and items later, step by step."
+      path_missing: "Choose how you want to start."
+      pack_section: "Set theme"
+      pack_hint: "Only changes the names of ranks and badges. The rules are the same everywhere."
+      pack_label: "Theme"
+      classes_section: "How many classes are you planning?"
+      classes_hint: "We'll fit the rank thresholds and prices so the highest rank is reachable within the semester."
+      classes_label: "Number of classes"
+      fewer_classes: "Fewer classes"
+      more_classes: "More classes"
+      summary: "Summary"
+      summary_hint: "The group will be created empty. After creating it you'll see a list of steps to complete."
+      summary_currency: "Currency"
+      summary_lives: "Starting lives"
+      summary_ranking: "Ranking"
+      card_preview: "Card in the group list"
+      you_lead: "You lead this group"
+      background_hint: "The background behind the form shows how the image looks as the group background."
+      currency_preview: "This is how students will see the currency"
+      back: "Back"
+      step_counter: "Step %{step} of %{total}"
+      submit: "Create group"
+      # group_wizard_controller.ts
+      js:
+        review_step: "Set review"
+        summary_step: "Summary"
+        counter: "Step %{step} of %{total}"
+        next: "Next"
+        create_short: "Create group"
+        create_quick: "Create group with the set"
+        create_empty: "Create an empty group"
+        name_placeholder: "Group name"
+        currency_placeholder: "Carrots"
+        ranking_off: "Off"
+        ranking_on: "Visible to students"
+
+    currency_mini:
+      to_spend: "to spend"
+
+    preset_review:
+      title: "The “%{pack}” set for %{classes} classes"
+      hint: "Remove what you don't need and adjust the numbers. You'll change names and descriptions after the group is created."
+      ranks: "Ranks"
+      starting_rank: "Starting rank"
+      shop_discount: "−%{discount}% in the shop"
+      from: "from"
+      from_zero: "from 0"
+      threshold_label: "%{name}: threshold"
+      badges: "Badges"
+      items: "Items in the shop"
+      price_label: "%{name}: price in %{currency}"
+      currency_fallback: "currency"
+      categories: "Class categories"
+      template: "(the “%{name}” template)"
+      reward_label: "%{name}: reward in %{currency}"
+
+    preset_row:
+      remove: "Remove: %{name}"
+      restore: "Restore: %{name}"
+
+    # StarterPack — written to the database in the teacher's language when the
+    # group is created. Numbers and icons stay in app/values/starter_pack.rb;
+    # every list here must keep its length and order.
+    starter_pack:
+      template_name: "Classes"
+      categories:
+        - "Attendance"
+        - "Punctuality"
+        - "Quiz passed"
+        - "Quiz ≥ group average"
+        - "Volunteered for a task"
+        - "Task done correctly"
+        - "Helping others"
+        - "Insightful remark"
+      badge_rules:
+        - "First quiz without mistakes"
+        - "Attended every class in a month"
+        - "Helped others at least 3 times"
+        - "At least 3 insightful remarks"
+        - "3 quizzes in a row ≥ group average"
+        - "Explained a hard task to the whole group"
+      items:
+        - name: "+5 minutes on a quiz"
+          didactic: "Adds 5 minutes to the time for the next quiz."
+        - name: "Consultation"
+          didactic: "A quarter-hour consultation with the teacher outside class."
+        - name: "Quiz retake"
+          didactic: "Lets you write one quiz again."
+        - name: "Safe retake"
+          didactic: "A risk-free quiz retake — the better of the two results counts."
+        - name: "Excuse note"
+          didactic: "Excuses one absence, without losing a life."
+        - name: "1up: get a life back"
+          didactic: "Restores one lost life."
+        - name: "+0.5 on the final grade"
+          didactic: "Raises the final grade by half a step."
+      packs:
+        neutral:
+          label: "Neutral"
+          description: "No story theme. Fits any subject."
+          ranks: ["Novice", "Learner", "Adept", "Expert", "Master"]
+          badges: ["Flawless", "Steady attendance", "Helping hand", "Spark of curiosity", "Winning streak", "Voice of the group"]
+        fantasy:
+          label: "Fantasy"
+          description: "Castles, orders and knightly titles."
+          ranks: ["Squire", "Knight", "Castellan", "Hetman", "King"]
+          badges: ["Clean blade", "Loyal guard", "Shield of the party", "Book of wisdom", "String of victories", "Bard of the party"]
+          badge_stories:
+            - "Steel without a scratch — the first duel won without a graze."
+            - "You stood guard every night this month."
+            - "Three times you shielded a companion with your own shield."
+            - "Three times you added something the books didn't have yet."
+            - "Three skirmishes in a row settled in your favour."
+            - "You explained to the whole party what nobody else could put into words."
+          item_stories:
+            - "The hourglass runs slower than it should."
+            - "An audience with the master of the order."
+            - "A second go at the duel."
+            - "A duel with blunt blades — losing costs nothing."
+            - "A safe-conduct letter explaining your absence."
+            - "A potion that restores a life."
+            - "The king's seal on your certificate."
+          category_stories:
+            - "You showed up at the muster."
+            - "In place before the horn sounded."
+            - "Trial of skill passed."
+            - "A score above the party average."
+            - "You volunteered."
+            - "Task done without fault."
+            - "You gave a companion a hand."
+            - "You shed light on something nobody had noticed."
+        scifi:
+          label: "Sci-fi"
+          description: "Ships, crews and space missions."
+          ranks: ["Cadet", "Pilot", "Navigator", "Commander", "Admiral"]
+          badges: ["Clean flight", "Always on board", "Crew mechanic", "Signal from space", "Mission streak", "Voice of the fleet"]
+          badge_stories:
+            - "The first flight without a single reading in the red."
+            - "Not a single shift missed this cycle."
+            - "Three times you got someone else's gear back on its feet."
+            - "Three times you caught a signal others missed."
+            - "Three missions in a row above the fleet standard."
+            - "Your explanation went out on the whole channel and everyone understood."
+          item_stories:
+            - "A brief slowdown of the ship's clock."
+            - "A call with the commander outside duty hours."
+            - "A second go at the simulation."
+            - "A training flight — a crash costs nothing."
+            - "A log entry excusing your absence."
+            - "Regeneration in the medical pod."
+            - "A promotion entered into the fleet records."
+          category_stories:
+            - "You reported on board."
+            - "At your station before the countdown."
+            - "Qualification test passed."
+            - "A score above the crew average."
+            - "You volunteered for a task."
+            - "Task done by the book."
+            - "You backed up another crew member."
+            - "You spotted something the sensors missed."
+
+  activerecord:
+    errors:
+      models:
+        story_group:
+          attributes:
+            name:
+              blank: "Enter the group name."
+            currency_name:
+              blank: "Enter the currency name."
diff --git a/config/locales/views/story_groups.pl.yml b/config/locales/views/story_groups.pl.yml
new file mode 100644
index 00000000..001f5cec
--- /dev/null
+++ b/config/locales/views/story_groups.pl.yml
@@ -0,0 +1,451 @@
+pl:
+  story_groups:
+    flash:
+      updated: "Zapisano ustawienia grupy."
+      destroyed: "Usunięto grupę %{name}."
+      duplicate_threshold: "Dwie rangi nie mogą mieć tego samego progu: %{first} i %{second} mają %{value}."
+
+    # StoryGroup.ranking_mode_label / #ranking_summary
+    ranking_modes:
+      podium_and_own: "Podium i własne miejsce"
+      full: "Pełny ranking"
+    ranking_off: "Wyłączony"
+
+    # StoryGroupsListing
+    listing:
+      roles:
+        own: "Prowadzisz"
+        sup: "Wspierasz"
+        lrn: "Uczysz się"
+      tabs:
+        all: "Wszystkie"
+        mine: "Moje"
+        teacher: "Nauczam"
+        student: "Uczę się"
+      owner: "Właściciel: %{name}"
+      no_purchases: "Brak nowych zakupów"
+      purchases:
+        one: "%{count} nowy zakup"
+        few: "%{count} nowe zakupy"
+        many: "%{count} nowych zakupów"
+        other: "%{count} nowego zakupu"
+      balance: "Masz %{balance} %{currency}"
+
+    # TeacherOverview
+    overview:
+      stats:
+        students: "Studenci"
+        purchases: "Zakupy w tym tygodniu"
+        purchases_note: "za %{amount}"
+        rewards: "Nagrody w tym tygodniu"
+        ranking: "Ranking"
+      zero_lives_title: "%{name} ma 0 żyć"
+      zero_lives_detail: "Kupi tylko przedmioty dostępne przy 0 życiach."
+      open: "Otwórz"
+      sheet_in_progress: "%{name} w trakcie"
+      sheet_awarded:
+        one: "Przyznano %{count} nagrodę"
+        few: "Przyznano %{count} nagrody"
+        many: "Przyznano %{count} nagród"
+        other: "Przyznano %{count} nagrody"
+      sheet_pending:
+        one: "%{count} kolumna bez ocen."
+        few: "%{count} kolumny bez ocen."
+        many: "%{count} kolumn bez ocen."
+        other: "%{count} kolumny bez ocen."
+      grade: "Oceń"
+
+    helpers:
+      teacher_lead:
+        one: "%{count} student w tej grupie. Dodaj opis w ustawieniach, żeby powitać nowe osoby."
+        few: "%{count} studenci w tej grupie. Dodaj opis w ustawieniach, żeby powitać nowe osoby."
+        many: "%{count} studentów w tej grupie. Dodaj opis w ustawieniach, żeby powitać nowe osoby."
+        other: "%{count} studenta w tej grupie. Dodaj opis w ustawieniach, żeby powitać nowe osoby."
+      next_rank: "Jeszcze %{missing} do rangi %{rank}."
+      next_rank_discount: "Ta ranga daje −%{discount}% w sklepie."
+      ranking_off: "Ranking jest wyłączony — studenci nie widzą tego podium."
+      ranking_full: "Studenci widzą pełny ranking, pod pseudonimami."
+      ranking_podium: "Studenci widzą podium i własne miejsce, pod pseudonimami."
+      place: "%{place}. miejsce w rankingu grupy"
+      hand:
+        one: "Dobierz coś w sklepie. Stać cię teraz na %{count} przedmiot."
+        few: "Dobierz coś w sklepie. Stać cię teraz na %{count} przedmioty."
+        many: "Dobierz coś w sklepie. Stać cię teraz na %{count} przedmiotów."
+        other: "Dobierz coś w sklepie. Stać cię teraz na %{count} przedmiotu."
+
+    index:
+      title: "Grupy"
+      student_lead: "Grupy, w których się uczysz."
+      teacher_lead: "Grupy, które prowadzisz, wspierasz albo w których się uczysz."
+      join: "Dołącz do grupy"
+      create: "Utwórz grupę"
+      filter: "Filtr grup"
+      search: "Szukaj grupy"
+      no_match: "Brak grup o nazwie"
+      no_match_hint: "Wyczyść wyszukiwanie albo sprawdź pisownię."
+      empty_tab_title: "Brak grup w tej zakładce"
+      empty_student_title: "Nie należysz jeszcze do żadnej grupy"
+      empty_title: "Nie masz jeszcze żadnej grupy"
+      empty_tab_body: "Zmień zakładkę, żeby zobaczyć pozostałe grupy."
+      empty_body: "Masz kod od prowadzącego? Dołącz do grupy jako uczestnik."
+
+    group_card:
+      students:
+        one: "%{count} student"
+        few: "%{count} studentów"
+        many: "%{count} studentów"
+        other: "%{count} studenta"
+
+    teacher_show:
+      show_code: "Pokaż kod dla studentów"
+      create_sheet: "Utwórz arkusz"
+      settings: "Ustawienia grupy"
+      summary: "Podsumowanie grupy"
+      purchases: "Ostatnie zakupy"
+      removed_item: "Przedmiot usunięty z oferty"
+      all_purchases: "Wszystkie zakupy w grupie"
+      no_purchases: "Nikt jeszcze niczego nie kupił. Zakupy pojawią się tutaj same, gdy studenci zaczną wydawać walutę w sklepie."
+      attention: "Wymaga uwagi"
+      recent_sheets: "Ostatnie arkusze"
+      open: "Otwórz"
+      no_rewards: "Nikt nie ma jeszcze nagród z tego arkusza."
+      no_sheets_title: "Nie masz jeszcze arkuszy ocen"
+      no_sheets_body: "Arkusz to jedne zajęcia: kolumny z nagrodami i lista studentów. Utwórz pierwszy, żeby zacząć przyznawać walutę."
+
+    student_show:
+      led_by: "Prowadzi %{name}"
+      balance_label: "Twoje %{currency}"
+      to_spend: "Do wydania"
+      collected: "Zebrane łącznie"
+      lives: "Życia"
+      open_shop: "Otwórz sklep"
+      your_rank: "Twoja ranga"
+      no_rank: "Brak rangi"
+      progress: "%{total} z %{needed}"
+      progress_label: "Postęp do następnej rangi"
+      top_rank: "%{total} zebranych. To najwyższa ranga w tej grupie."
+      no_ranks: "Prowadzący nie dodał jeszcze rang. Waluta, którą zbierasz, liczy się mimo to — rangi przyznają się same, gdy się pojawią."
+      badges: "Odznaki"
+      badges_count: "%{earned} z %{total}"
+      items: "Twoje przedmioty"
+      go_to_shop: "Przejdź do sklepu"
+      recent: "Ostatnie zmiany"
+      entry_meta: "%{label}, %{when}"
+      full_history: "Pokaż całą historię"
+      no_entries: "Pierwsze wpisy pojawią się po zajęciach. Prowadzący przyznaje walutę za obecność, punktualność i aktywność."
+
+    new:
+      page_title: "Nowa grupa"
+
+    edit:
+      page_title: "Ustawienia grupy - %{name}"
+
+    created:
+      page_title: "Grupa %{name} jest gotowa"
+      title: "Grupa „%{name}” jest gotowa"
+      ranks:
+        one: "%{count} rangę"
+        few: "%{count} rangi"
+        many: "%{count} rang"
+        other: "%{count} rangi"
+      badges:
+        one: "%{count} odznakę"
+        few: "%{count} odznaki"
+        many: "%{count} odznak"
+        other: "%{count} odznaki"
+      items:
+        one: "%{count} przedmiot"
+        few: "%{count} przedmioty"
+        many: "%{count} przedmiotów"
+        other: "%{count} przedmiotu"
+      categories:
+        one: "%{count} kategorię w szablonie arkusza"
+        few: "%{count} kategorie w szablonie arkusza"
+        many: "%{count} kategorii w szablonie arkusza"
+        other: "%{count} kategorii w szablonie arkusza"
+      quick_lead: "Utworzono %{list}."
+      empty_lead: "Grupa jest pusta. Poniżej znajdziesz kolejne kroki."
+      invites_note_html: "Kod do dołączenia utworzysz w zakładce %{tab}, kiedy będziesz go potrzebować. Możesz mieć kilka kodów naraz, z limitem osób albo datą ważności."
+      invites_tab: "Zaproszenia"
+      next: "Co dalej"
+      quick_steps:
+        - "Zaproś studentów: pokaż im kod albo kod QR."
+        - "Po pierwszych zajęciach utwórz arkusz ocen i oceń studentów."
+        - "Zajrzyj do sklepu i dopasuj opisy przedmiotów do swojej opowieści."
+      empty_steps:
+        - "Dodaj rangi, żeby studenci widzieli, do czego dążą."
+        - "Dodaj przedmioty do sklepu."
+        - "Dodaj odznaki za szczególne osiągnięcia."
+        - "Utwórz szablon arkusza ocen."
+        - "Zaproś studentów: pokaż im kod albo kod QR."
+      go_to_group: "Przejdź do grupy"
+      create_invite: "Utwórz zaproszenie"
+
+    confirm_destroy:
+      page_title: "Usuń grupę %{name}"
+      title: "Usunąć grupę na zawsze?"
+      students:
+        one: "%{count} student"
+        few: "%{count} studenci"
+        many: "%{count} studentów"
+        other: "%{count} studenta"
+      teachers:
+        one: "%{count} nauczyciel"
+        few: "%{count} nauczycieli"
+        many: "%{count} nauczycieli"
+        other: "%{count} nauczyciela"
+      lose_access:
+        one: "%{students} i %{teachers} straci dostęp."
+        few: "%{students} i %{teachers} stracą dostęp."
+        many: "%{students} i %{teachers} straci dostęp."
+        other: "%{students} i %{teachers} straci dostęp."
+      gone: "Historia, przedmioty i ranking znikną."
+      confirm: "Wpisz nazwę grupy, żeby potwierdzić:"
+      mismatch: "Wpisana nazwa nie zgadza się z nazwą grupy. Grupa nie została usunięta."
+      remove: "Usuń grupę"
+
+    settings:
+      title: "Ustawienia grupy"
+      lead: "Zmienią je wszyscy prowadzący tę grupę. Tylko właściciel może usunąć grupę. Ranking ustawiasz w zakładce Ranking."
+      group_section: "Grupa i opowieść"
+      name: "Nazwa grupy"
+      name_placeholder: "np. Kosmiczne króliki"
+      story: "Opowieść"
+      story_hint: "Widzą ją wszyscy w grupie, na stronie głównej grupy."
+      art_label: "Grafika grupy"
+      art_hint: "JPG lub PNG, najlepiej co najmniej 1200 px szerokości."
+      currency_section: "Waluta"
+      currency_hint: "Nowa nazwa pojawi się wszędzie, także w historii studentów."
+      currency_name: "Nazwa waluty"
+      currency_placeholder: "np. Marchewek"
+      currency_name_hint: "Podaj ją w formie, która pasuje do liczby — np. „Marchewek”."
+      lives_section: "Życia"
+      lives: "Życia na start"
+      lives_hint: "Dotyczy tylko studentów, którzy dołączą od teraz. Obecnym zmieniasz życia na liście studentów."
+      back: "Wróć do grupy"
+      delete_title: "Usuń grupę"
+      delete_body: "Usunięcie zabiera wszystkim dostęp do grupy, jej sklepu, rankingu i historii. Tego nie da się cofnąć."
+      delete: "Usuń grupę"
+
+    # Shared by the wizard and the settings form (shared/_image_field).
+    currency_icon:
+      label: "Ikona waluty"
+      presets: "Gotowe ikony"
+      own: "Twoja ikona"
+      upload: "Albo wgraj własną ikonę"
+      hint: "Najlepiej PNG z przezroczystym tłem, co najmniej 128 px."
+      crop: "Przytnij ikonę"
+      cropped: "Przesuń i przeskaluj zaznaczenie. Zapisujemy kwadratowy kadr, bo ikona siada na okrągłym liczmanie."
+
+    wizard:
+      steps:
+        - "Grupa i opowieść"
+        - "Waluta i zasady"
+        - "Jak zaczynasz"
+        - "Podsumowanie"
+      breadcrumb: "Grupy"
+      title: "Nowa grupa"
+      lead: "Zajmie to kilka minut. Wszystko zmienisz później w ustawieniach grupy."
+      steps_label: "Kroki"
+      name_section: "Nazwa i opowieść"
+      name_hint: "Studenci zobaczą je na liście grup i na stronie grupy."
+      name: "Nazwa grupy"
+      name_placeholder: "np. Zakon Algorytmów"
+      name_missing: "Podaj nazwę grupy."
+      story: "Opowieść"
+      story_placeholder: "Dawno, dawno temu…"
+      story_hint: "Krótki wstęp fabularny. Zmienisz go w każdej chwili."
+      art_section: "Grafika grupy"
+      art_hint: "Pojawia się na karcie grupy, w panelu bocznym i jako tło grupy."
+      currency_section: "Nazwa waluty"
+      currency_hint: "Czytamy ją po każdej liczbie, więc podaj formę, która pasuje do liczby mnogiej — np. „Marchewek”."
+      currency_name: "Nazwa waluty"
+      currency_placeholder: "np. Złotych Monet"
+      currency_missing: "Podaj nazwę waluty."
+      lives_section: "Życia"
+      lives: "Życia na start"
+      fewer_lives: "Mniej żyć"
+      more_lives: "Więcej żyć"
+      lives_hint: "Przy 0 życiach student kupi tylko przedmioty oznaczone jako dostępne przy 0 życiach."
+      ranking_section: "Ranking"
+      ranking: "Pokazuj ranking studentom"
+      ranking_hint: "Domyślnie wyłączony. Możesz go włączyć w każdej chwili w zakładce Ranking."
+      ranking_mode: "Co widzą studenci"
+      ranking_mode_hint: "„Podium i własne miejsce” pokazuje tylko najlepszą trójkę i miejsce studenta. „Pełny ranking” pokazuje całą listę."
+      start_section: "Jak chcesz zacząć?"
+      start_hint: "Obie drogi dają pełną grupę. Wszystko zmienisz później."
+      start_label: "Sposób startu"
+      recommended: "Polecane na pierwszą grupę"
+      quick: "Szybki start"
+      quick_body: "Gotowe rangi, odznaki, przedmioty i kategorie zajęć. Przejrzysz je i poprawisz przed utworzeniem grupy."
+      manual: "Od zera"
+      manual_body: "Pusta grupa. Rangi, odznaki i przedmioty dodasz później, krok po kroku."
+      path_missing: "Wybierz, jak chcesz zacząć."
+      pack_section: "Klimat zestawu"
+      pack_hint: "Zmienia tylko nazwy rang i odznak. Zasady są wszędzie takie same."
+      pack_label: "Klimat"
+      classes_section: "Ile zajęć planujesz?"
+      classes_hint: "Dopasujemy progi rang i ceny tak, żeby najwyższa ranga była osiągalna w semestrze."
+      classes_label: "Liczba zajęć"
+      fewer_classes: "Mniej zajęć"
+      more_classes: "Więcej zajęć"
+      summary: "Podsumowanie"
+      summary_hint: "Grupa powstanie pusta. Po utworzeniu zobaczysz listę kroków do uzupełnienia."
+      summary_currency: "Waluta"
+      summary_lives: "Życia na start"
+      summary_ranking: "Ranking"
+      card_preview: "Karta na liście grup"
+      you_lead: "Prowadzisz tę grupę"
+      background_hint: "Tło za formularzem pokazuje, jak grafika wygląda jako tło grupy."
+      currency_preview: "Tak zobaczą walutę studenci"
+      back: "Wstecz"
+      step_counter: "Krok %{step} z %{total}"
+      submit: "Utwórz grupę"
+      # group_wizard_controller.ts
+      js:
+        review_step: "Przegląd zestawu"
+        summary_step: "Podsumowanie"
+        counter: "Krok %{step} z %{total}"
+        next: "Dalej"
+        create_short: "Utwórz grupę"
+        create_quick: "Utwórz grupę z zestawem"
+        create_empty: "Utwórz pustą grupę"
+        name_placeholder: "Nazwa grupy"
+        currency_placeholder: "Marchewek"
+        ranking_off: "Wyłączony"
+        ranking_on: "Widoczny dla studentów"
+
+    currency_mini:
+      to_spend: "do wydania"
+
+    preset_review:
+      title: "Zestaw „%{pack}” dla %{classes} zajęć"
+      hint: "Usuń, czego nie potrzebujesz, i popraw liczby. Nazwy i opisy zmienisz po utworzeniu grupy."
+      ranks: "Rangi"
+      starting_rank: "Ranga startowa"
+      shop_discount: "−%{discount}% w sklepie"
+      from: "od"
+      from_zero: "od 0"
+      threshold_label: "%{name}: próg"
+      badges: "Odznaki"
+      items: "Przedmioty w sklepie"
+      price_label: "%{name}: cena w %{currency}"
+      currency_fallback: "waluty"
+      categories: "Kategorie zajęć"
+      template: "(szablon „%{name}”)"
+      reward_label: "%{name}: nagroda w %{currency}"
+
+    preset_row:
+      remove: "Usuń: %{name}"
+      restore: "Przywróć: %{name}"
+
+    # StarterPack — written to the database in the teacher's language when the
+    # group is created. Numbers and icons stay in app/values/starter_pack.rb;
+    # every list here must keep its length and order.
+    starter_pack:
+      template_name: "Zajęcia"
+      categories:
+        - "Obecność"
+        - "Punktualność"
+        - "Wejściówka zaliczona"
+        - "Wejściówka ≥ średnia grupy"
+        - "Zgłoszenie do zadania"
+        - "Zadanie zrobione poprawnie"
+        - "Pomoc innym"
+        - "Ciekawa uwaga"
+      badge_rules:
+        - "Pierwsza wejściówka bez błędów"
+        - "Obecność na wszystkich zajęciach w miesiącu"
+        - "Co najmniej 3 razy pomógł innym"
+        - "Co najmniej 3 ciekawe uwagi"
+        - "3 wejściówki z rzędu ≥ średniej grupy"
+        - "Wyjaśnienie trudnego zadania całej grupie"
+      items:
+        - name: "+5 minut do wejściówki"
+          didactic: "Dodaje 5 minut do czasu na najbliższą wejściówkę."
+        - name: "Konsultacja"
+          didactic: "Kwadrans konsultacji z prowadzącym poza zajęciami."
+        - name: "Poprawa wejściówki"
+          didactic: "Pozwala napisać jedną wejściówkę jeszcze raz."
+        - name: "Bezpieczna poprawa"
+          didactic: "Poprawa wejściówki bez ryzyka — liczy się lepszy z dwóch wyników."
+        - name: "Usprawiedliwienie"
+          didactic: "Usprawiedliwia jedną nieobecność, bez utraty życia."
+        - name: "1up: odzyskanie życia"
+          didactic: "Przywraca jedno utracone życie."
+        - name: "+0.5 oceny końcowej"
+          didactic: "Podnosi ocenę końcową o pół stopnia."
+      packs:
+        neutral:
+          label: "Neutralny"
+          description: "Bez fabularnego klimatu. Pasuje do każdego przedmiotu."
+          ranks: ["Nowicjusz", "Uczeń", "Adept", "Ekspert", "Mistrz"]
+          badges: ["Bez skazy", "Stała obecność", "Pomocna dłoń", "Iskra ciekawości", "Seria sukcesów", "Głos grupy"]
+        fantasy:
+          label: "Fantasy"
+          description: "Zamki, zakony i rycerskie tytuły."
+          ranks: ["Giermek", "Rycerz", "Kasztelan", "Hetman", "Król"]
+          badges: ["Czysta klinga", "Wierna straż", "Tarcza drużyny", "Księga mądrości", "Pasmo zwycięstw", "Bard drużyny"]
+          badge_stories:
+            - "Stal bez jednej rysy — pierwszy pojedynek wygrany bez draśnięcia."
+            - "Stałeś na posterunku każdej nocy tego miesiąca."
+            - "Trzykrotnie zasłoniłeś towarzysza własną tarczą."
+            - "Trzy razy dopisałeś coś, czego w księgach jeszcze nie było."
+            - "Trzy potyczki z rzędu rozstrzygnięte na twoją korzyść."
+            - "Wytłumaczyłeś całej drużynie to, czego nikt inny nie potrafił nazwać."
+          item_stories:
+            - "Klepsydra sypie piaskiem wolniej, niż powinna."
+            - "Audiencja u mistrza zakonu."
+            - "Drugie podejście do pojedynku."
+            - "Pojedynek na tępe klingi — przegrana nic nie kosztuje."
+            - "List żelazny tłumaczący twoją nieobecność."
+            - "Eliksir przywracający życie."
+            - "Pieczęć króla na twoim świadectwie."
+          category_stories:
+            - "Stawiłeś się na zbiórce."
+            - "Na miejscu, zanim zabrzmiał róg."
+            - "Próba sprawności zaliczona."
+            - "Wynik powyżej średniej drużyny."
+            - "Zgłosiłeś się na ochotnika."
+            - "Zadanie wykonane bez zarzutu."
+            - "Podałeś rękę towarzyszowi."
+            - "Rzuciłeś światło na rzecz, której nikt nie dostrzegł."
+        scifi:
+          label: "Sci-fi"
+          description: "Statki, załogi i kosmiczne misje."
+          ranks: ["Kadet", "Pilot", "Nawigator", "Komandor", "Admirał"]
+          badges: ["Czysty lot", "Zawsze na pokładzie", "Mechanik załogi", "Sygnał z kosmosu", "Seria misji", "Głos floty"]
+          badge_stories:
+            - "Pierwszy lot bez jednego odczytu w czerwieni."
+            - "Ani jednej zmiany opuszczonej w tym cyklu."
+            - "Trzy razy postawiłeś na nogi cudzy sprzęt."
+            - "Trzy razy wychwyciłeś sygnał, który inni przegapili."
+            - "Trzy misje z rzędu zaliczone powyżej normy floty."
+            - "Twoje wyjaśnienie poszło na cały kanał i wszyscy zrozumieli."
+          item_stories:
+            - "Chwilowe spowolnienie zegara pokładowego."
+            - "Połączenie z komandorem poza godzinami służby."
+            - "Drugie podejście do symulacji."
+            - "Lot treningowy — awaria nic nie kosztuje."
+            - "Wpis do dziennika usprawiedliwiający nieobecność."
+            - "Regeneracja w kapsule medycznej."
+            - "Awans wpisany do akt floty."
+          category_stories:
+            - "Zameldowałeś się na pokładzie."
+            - "Na stanowisku przed odliczaniem."
+            - "Test kwalifikacyjny zaliczony."
+            - "Wynik powyżej średniej załogi."
+            - "Zgłosiłeś się do zadania."
+            - "Zadanie wykonane zgodnie z procedurą."
+            - "Wsparłeś innego członka załogi."
+            - "Zauważyłeś coś, co umknęło czujnikom."
+
+  activerecord:
+    errors:
+      models:
+        story_group:
+          attributes:
+            name:
+              blank: "Podaj nazwę grupy."
+            currency_name:
+              blank: "Podaj nazwę waluty."
diff --git a/config/locales/views/students.en.yml b/config/locales/views/students.en.yml
new file mode 100644
index 00000000..e6d6b3fa
--- /dev/null
+++ b/config/locales/views/students.en.yml
@@ -0,0 +1,117 @@
+en:
+  students:
+    flash:
+      lives_notice:
+        one: "%{name} now has %{count} life."
+        other: "%{name} now has %{count} lives."
+      cannot_take_life: "Can't take a life — the student already has 0."
+      removed: "%{name} is no longer in the group."
+
+    helpers:
+      list_lead: "You take a life for an unexcused absence."
+      zero_lives:
+        one: "%{count} student has 0 lives"
+        other: "%{count} students have 0 lives"
+      zero_lives_tail: "and can only buy items available at 0 lives."
+      nickname_quoted: "“%{nickname}”"
+      nickname: "Nickname: %{nickname}"
+      university_number: "student no. %{number}"
+      rank_progress: "%{total} of %{required} to the %{rank} rank"
+      losses:
+        badges:
+          one: "%{count} badge"
+          other: "%{count} badges"
+        items:
+          one: "%{count} item"
+          other: "%{count} items"
+        ledger:
+          one: "the whole currency history (%{count} entry)"
+          other: "the whole currency history (%{count} entries)"
+
+    index:
+      title: "Students"
+      invites: "Codes and invites"
+      show_code: "Show code to students"
+      search: "Search for a student"
+      of: "of"
+      count: "%{shown} of %{total}"
+      columns:
+        student: "Student"
+        rank: "Rank"
+        lives: "Lives"
+        balance: "To spend"
+        total: "Collected"
+        badges: "Badges"
+        actions: "Actions"
+      no_match: "No students named"
+      no_match_hint: "Clear the search or check the spelling."
+      empty_title: "Nobody has joined the group yet"
+      empty_body: "Send students a code or an invite — once they join, they will show up here with their rank, currency and lives."
+
+    row:
+      rank: "Rank"
+      lives: "Lives"
+      balance: "To spend"
+      total: "Collected"
+      badges: "Badges"
+      take_life: "Take a life: %{name}"
+      add_life: "Add a life: %{name}"
+      award_badge: "Award a badge"
+      award_badge_for: "Award a badge: %{name}"
+      adjust_currency: "Adjust currency"
+      adjust_currency_for: "Adjust currency: %{name}"
+      history: "Transaction history"
+      history_for: "History: %{name}"
+
+    show:
+      breadcrumb: "Students"
+      award_badge: "Award a badge"
+      adjust_currency: "Adjust currency"
+      rank: "Rank"
+      rank_progress_label: "Progress to the %{rank} rank"
+      balance: "To spend"
+      total: "Collected in total"
+      lives: "Lives"
+      sections: "Student sections"
+      tabs:
+        badges: "Badges"
+        items: "Items"
+        hist: "Currency history"
+
+    edit:
+      page_title: "Edit student - %{name}"
+
+    form:
+      title: "Edit student"
+      account_note: "The name and e-mail come from the student's account."
+      lives: "Lives"
+      take_life: "Take a life"
+      add_life: "Add a life"
+      lives_hint: "You take a life for an unexcused absence. At 0 lives the student can only buy items available at 0 lives."
+      remove_label: "Remove from group"
+      remove_hint: "The student will lose access to the group, and their badges, items and currency history will be lost. They can only rejoin with a new code."
+      remove: "Remove from group"
+
+    confirm_destroy:
+      page_title: "Remove from group - %{name}"
+      title: "Remove the student from the group?"
+      access_lost: "%{name} will lose access to the group and disappear from lists, the ranking and grade sheets."
+      losses: "Lost: %{list}."
+      irreversible: "This can't be undone."
+      nothing_to_lose: "This student has no badges, items or currency history yet."
+      rejoin_note: "If they rejoin the group, they will get a new member account and start from scratch."
+      remove: "Remove from group"
+
+    tab_badges:
+      removed: "Removed from the list"
+      awarded: "Awarded %{when}"
+      revoke: "Revoke"
+      revoke_label: "Revoke badge %{name}"
+      empty: "The student has no badges yet."
+
+    tab_history:
+      empty: "No entries of this type."
+
+    tab_items:
+      intro: "Items bought in the shop. You settle the use of an item (e.g. a quiz retake) in class."
+      empty: "The student hasn't bought anything yet. Items will show up here with the price they paid."
diff --git a/config/locales/views/students.pl.yml b/config/locales/views/students.pl.yml
new file mode 100644
index 00000000..8e7ef7a7
--- /dev/null
+++ b/config/locales/views/students.pl.yml
@@ -0,0 +1,127 @@
+pl:
+  students:
+    flash:
+      lives_notice:
+        one: "%{name} ma teraz %{count} życie."
+        few: "%{name} ma teraz %{count} życia."
+        many: "%{name} ma teraz %{count} żyć."
+        other: "%{name} ma teraz %{count} życia."
+      cannot_take_life: "Nie można odebrać życia — student ma już 0."
+      removed: "%{name} nie należy już do grupy."
+
+    helpers:
+      list_lead: "Życie odbierasz za nieusprawiedliwioną nieobecność."
+      zero_lives:
+        one: "%{count} student ma 0 żyć"
+        few: "%{count} studentów ma 0 żyć"
+        many: "%{count} studentów ma 0 żyć"
+        other: "%{count} studentów ma 0 żyć"
+      zero_lives_tail: "i kupi tylko przedmioty dostępne przy 0 życiach."
+      nickname_quoted: "„%{nickname}”"
+      nickname: "Pseudonim: %{nickname}"
+      university_number: "indeks %{number}"
+      rank_progress: "%{total} z %{required} do rangi %{rank}"
+      losses:
+        badges:
+          one: "%{count} odznakę"
+          few: "%{count} odznaki"
+          many: "%{count} odznak"
+          other: "%{count} odznaki"
+        items:
+          one: "%{count} przedmiot"
+          few: "%{count} przedmioty"
+          many: "%{count} przedmiotów"
+          other: "%{count} przedmiotu"
+        ledger:
+          one: "całą historię waluty (%{count} wpis)"
+          few: "całą historię waluty (%{count} wpisy)"
+          many: "całą historię waluty (%{count} wpisów)"
+          other: "całą historię waluty (%{count} wpisu)"
+
+    index:
+      title: "Studenci"
+      invites: "Kody i zaproszenia"
+      show_code: "Pokaż kod dla studentów"
+      search: "Szukaj studenta"
+      of: "z"
+      count: "%{shown} z %{total}"
+      columns:
+        student: "Student"
+        rank: "Ranga"
+        lives: "Życia"
+        balance: "Do wydania"
+        total: "Zebrane"
+        badges: "Odznaki"
+        actions: "Akcje"
+      no_match: "Brak studentów o nazwie"
+      no_match_hint: "Wyczyść wyszukiwanie albo sprawdź pisownię."
+      empty_title: "Nie ma jeszcze nikogo w grupie"
+      empty_body: "Wyślij studentom kod albo zaproszenie — kiedy dołączą, pojawią się tutaj razem z rangą, walutą i życiami."
+
+    row:
+      rank: "Ranga"
+      lives: "Życia"
+      balance: "Do wydania"
+      total: "Zebrane"
+      badges: "Odznaki"
+      take_life: "Odbierz życie: %{name}"
+      add_life: "Dodaj życie: %{name}"
+      award_badge: "Przyznaj odznakę"
+      award_badge_for: "Przyznaj odznakę: %{name}"
+      adjust_currency: "Koryguj walutę"
+      adjust_currency_for: "Koryguj walutę: %{name}"
+      history: "Historia transakcji"
+      history_for: "Historia: %{name}"
+
+    show:
+      breadcrumb: "Studenci"
+      award_badge: "Przyznaj odznakę"
+      adjust_currency: "Koryguj walutę"
+      rank: "Ranga"
+      rank_progress_label: "Postęp do rangi %{rank}"
+      balance: "Do wydania"
+      total: "Zebrane łącznie"
+      lives: "Życia"
+      sections: "Sekcje studenta"
+      tabs:
+        badges: "Odznaki"
+        items: "Przedmioty"
+        hist: "Historia waluty"
+
+    edit:
+      page_title: "Edytuj studenta - %{name}"
+
+    form:
+      title: "Edytuj studenta"
+      account_note: "Imię, nazwisko i e-mail pochodzą z konta studenta."
+      lives: "Życia"
+      take_life: "Odbierz życie"
+      add_life: "Dodaj życie"
+      lives_hint: "Życie odbierasz za nieusprawiedliwioną nieobecność. Przy 0 życiach student kupi tylko przedmioty dostępne przy 0 życiach."
+      remove_label: "Usuń z grupy"
+      remove_hint: "Student straci dostęp do grupy, a jego odznaki, przedmioty i historia waluty przepadną. Dołączy ponownie tylko z nowym kodem."
+      remove: "Usuń z grupy"
+
+    confirm_destroy:
+      page_title: "Usuń z grupy - %{name}"
+      title: "Usunąć studenta z grupy?"
+      access_lost: "%{name} straci dostęp do grupy i zniknie z list, rankingu i arkuszy ocen."
+      losses: "Przepadną: %{list}."
+      irreversible: "Tego nie da się cofnąć."
+      nothing_to_lose: "Ten student nie ma jeszcze odznak, przedmiotów ani historii waluty."
+      rejoin_note: "Jeśli wróci do grupy, dostanie nowe konto uczestnika i zacznie od zera."
+      remove: "Usuń z grupy"
+
+    tab_badges:
+      removed: "Usunięta z listy"
+      awarded: "Przyznana %{when}"
+      revoke: "Odbierz"
+      revoke_label: "Odbierz odznakę %{name}"
+      empty: "Student nie ma jeszcze żadnej odznaki."
+
+    tab_history:
+      empty: "Brak wpisów tego typu."
+
+    tab_items:
+      intro: "Przedmioty kupione w sklepie. Wykorzystanie przedmiotu (np. poprawę wejściówki) rozliczasz na zajęciach."
+      empty: "Student nic jeszcze nie kupił. Przedmioty pojawią się tu razem z ceną, jaką zapłacił."
diff --git a/config/locales/views/students_activity_group_categories.en.yml b/config/locales/views/students_activity_group_categories.en.yml
new file mode 100644
index 00000000..fd461f0a
--- /dev/null
+++ b/config/locales/views/students_activity_group_categories.en.yml
@@ -0,0 +1,65 @@
+en:
+  # The grading table ("Ocenianie").
+  students_activity_group_categories:
+    flash:
+      nothing: "No cells were marked."
+      awarded:
+        one: "Awarded %{total} %{currency} to %{count} student."
+        other: "Awarded %{total} %{currency} to %{count} students."
+
+    edit:
+      lead:
+        one: "%{categories}, %{count} student. Mark who earned rewards — you'll review everything once more before awarding."
+        other: "%{categories}, %{count} students. Mark who earned rewards — you'll review everything once more before awarding."
+      categories:
+        one: "%{count} category"
+        other: "%{count} categories"
+      search: "Search for a student"
+      legend: "Legend"
+      empty: "Empty"
+      marked_now: "Marked now"
+      awarded_locked: "Awarded, can't be undone"
+      student: "Student"
+      select_column: "Mark the whole column"
+      everyone: "Everyone"
+      total: "Total"
+      locked_title: "Awarded, can't be undone"
+      cell_awarded: "%{label}: awarded"
+      cell_empty: "%{label}: empty"
+      nothing_marked: "Nothing is marked. Click the cells of students who earned rewards."
+      clear: "Clear marks"
+      review: "Review and award"
+      no_columns_title: "This sheet has no columns"
+      no_columns_body: "Add columns in the sheet settings so there's something to reward."
+      sheet_settings: "Sheet settings"
+      no_students_title: "There are no students in this group yet"
+      no_students_body: "Invite students to the group — the sheet is ready and nothing in it gets lost."
+      invites: "Invites"
+      mobile_body: "Grading in the table works on a computer. This table has %{categories} and %{students}, so it would be unreadable on a phone."
+      mobile_categories:
+        one: "%{count} category"
+        other: "%{count} categories"
+      mobile_students:
+        one: "%{count} student"
+        other: "%{count} students"
+      mobile_hint: "On your phone you can check recent purchases and notifications."
+      back_home: "Back to home"
+      # grading_controller.ts
+      js:
+        cells:
+          one: "Marked now: %{count} cell"
+          other: "Marked now: %{count} cells"
+        students:
+          one: "for %{count} student, total"
+          other: "for %{count} students, total"
+        recipients:
+          one: "to %{count} student"
+          other: "to %{count} students"
+        cell_empty: "%{label}: empty"
+        cell_marked: "%{label}: marked"
+        locked: "This cell is already awarded and can't be undone."
+
+    review_dialog:
+      awarding: "You're awarding"
+      warning: "Once confirmed, this can't be undone. Check the list before awarding rewards."
+      confirm: "Award"
diff --git a/config/locales/views/students_activity_group_categories.pl.yml b/config/locales/views/students_activity_group_categories.pl.yml
new file mode 100644
index 00000000..48a025c2
--- /dev/null
+++ b/config/locales/views/students_activity_group_categories.pl.yml
@@ -0,0 +1,81 @@
+pl:
+  # The grading table ("Ocenianie").
+  students_activity_group_categories:
+    flash:
+      nothing: "Nie zaznaczono żadnego pola."
+      awarded:
+        one: "Przyznano %{total} %{currency} %{count} studentowi."
+        few: "Przyznano %{total} %{currency} %{count} studentom."
+        many: "Przyznano %{total} %{currency} %{count} studentom."
+        other: "Przyznano %{total} %{currency} %{count} studenta."
+
+    edit:
+      lead:
+        one: "%{categories}, %{count} student. Zaznacz, kto zdobył nagrody, a przed przyznaniem przejrzysz wszystko jeszcze raz."
+        few: "%{categories}, %{count} studentów. Zaznacz, kto zdobył nagrody, a przed przyznaniem przejrzysz wszystko jeszcze raz."
+        many: "%{categories}, %{count} studentów. Zaznacz, kto zdobył nagrody, a przed przyznaniem przejrzysz wszystko jeszcze raz."
+        other: "%{categories}, %{count} studenta. Zaznacz, kto zdobył nagrody, a przed przyznaniem przejrzysz wszystko jeszcze raz."
+      categories:
+        one: "%{count} kategoria"
+        few: "%{count} kategorie"
+        many: "%{count} kategorii"
+        other: "%{count} kategorii"
+      search: "Szukaj studenta"
+      legend: "Legenda"
+      empty: "Puste"
+      marked_now: "Zaznaczone teraz"
+      awarded_locked: "Przyznane, nie do cofnięcia"
+      student: "Student"
+      select_column: "Zaznacz całą kolumnę"
+      everyone: "Wszyscy"
+      total: "Razem"
+      locked_title: "Przyznane, nie można cofnąć"
+      cell_awarded: "%{label}: przyznane"
+      cell_empty: "%{label}: puste"
+      nothing_marked: "Nic nie jest zaznaczone. Kliknij pola studentów, którzy zdobyli nagrody."
+      clear: "Wyczyść zaznaczenia"
+      review: "Przejrzyj i przyznaj"
+      no_columns_title: "Ten arkusz nie ma żadnej kolumny"
+      no_columns_body: "Dodaj kolumny w ustawieniach arkusza, żeby było za co nagradzać."
+      sheet_settings: "Ustawienia arkusza"
+      no_students_title: "W tej grupie nie ma jeszcze studentów"
+      no_students_body: "Zaproś studentów do grupy — arkusz czeka gotowy i nic w nim nie przepada."
+      invites: "Zaproszenia"
+      mobile_body: "Ocenianie w tabeli działa na komputerze. Ta tabela ma %{categories} i %{students}, więc na telefonie byłaby nieczytelna."
+      mobile_categories:
+        one: "%{count} kategorię"
+        few: "%{count} kategorie"
+        many: "%{count} kategorii"
+        other: "%{count} kategorii"
+      mobile_students:
+        one: "%{count} studenta"
+        few: "%{count} studentów"
+        many: "%{count} studentów"
+        other: "%{count} studenta"
+      mobile_hint: "Na telefonie sprawdzisz ostatnie zakupy i powiadomienia."
+      back_home: "Wróć na start"
+      # grading_controller.ts
+      js:
+        cells:
+          one: "Zaznaczone teraz: %{count} pole"
+          few: "Zaznaczone teraz: %{count} pola"
+          many: "Zaznaczone teraz: %{count} pól"
+          other: "Zaznaczone teraz: %{count} pola"
+        students:
+          one: "u %{count} studenta, razem"
+          few: "u %{count} studentów, razem"
+          many: "u %{count} studentów, razem"
+          other: "u %{count} studenta, razem"
+        recipients:
+          one: "%{count} studentowi"
+          few: "%{count} studentom"
+          many: "%{count} studentom"
+          other: "%{count} studenta"
+        cell_empty: "%{label}: puste"
+        cell_marked: "%{label}: zaznaczone"
+        locked: "To pole jest już przyznane i nie można go cofnąć."
+
+    review_dialog:
+      awarding: "Przyznajesz"
+      warning: "Po zatwierdzeniu nie da się tego cofnąć. Sprawdź listę, zanim przyznasz nagrody."
+      confirm: "Przyznaj"
diff --git a/config/locales/views/students_badges.en.yml b/config/locales/views/students_badges.en.yml
new file mode 100644
index 00000000..2cdd9606
--- /dev/null
+++ b/config/locales/views/students_badges.en.yml
@@ -0,0 +1,33 @@
+en:
+  students_badges:
+    flash:
+      awarded: "Awarded the “%{name}” badge."
+      revoked: "Revoked the “%{name}” badge."
+
+    helpers:
+      assign_lead:
+        one: "%{name} has %{held} of %{count} badge."
+        other: "%{name} has %{held} of %{count} badges."
+      owned: "Already has it"
+      effect_html: "Once awarded: %{discount} on items that count this badge%{discounting}.%{unlocks} They will see it in their deck."
+      effect_discounting: " (%{items})"
+      effect_unlocks_html: " Unlocks buying: %{items}."
+      revoke_html: "%{name} will lose the %{discount} discount%{unlocking}. Items bought earlier stay."
+      revoke_unlocking: " and the option to buy: %{items}"
+
+    new:
+      page_title: "Award a badge - %{name}"
+
+    form:
+      pick: "Award"
+      blank: "Choose a badge"
+      title: "Award a badge"
+      search: "Search for a badge"
+      no_match: "No badges with that name."
+      empty: "This group has no badges yet. Add them in the Badges tab, then come back here."
+      submit: "Choose a badge"
+
+    confirm_destroy:
+      page_title: "Revoke badge %{name}"
+      title: "Revoke the “%{name}” badge?"
+      revoke: "Revoke badge"
diff --git a/config/locales/views/students_badges.pl.yml b/config/locales/views/students_badges.pl.yml
new file mode 100644
index 00000000..8de294f0
--- /dev/null
+++ b/config/locales/views/students_badges.pl.yml
@@ -0,0 +1,36 @@
+pl:
+  students_badges:
+    flash:
+      awarded: "Przyznano odznakę „%{name}”."
+      revoked: "Odebrano odznakę „%{name}”."
+
+    helpers:
+      # The form follows the total: "z 1 odznaki", "z 3 odznak".
+      assign_lead:
+        one: "%{name} ma %{held} z %{count} odznaki."
+        few: "%{name} ma %{held} z %{count} odznak."
+        many: "%{name} ma %{held} z %{count} odznak."
+        other: "%{name} ma %{held} z %{count} odznaki."
+      owned: "Ma już"
+      effect_html: "Po przyznaniu: %{discount} na przedmioty, które uwzględniają tę odznakę%{discounting}.%{unlocks} Zobaczy ją w swojej talii."
+      effect_discounting: " (%{items})"
+      effect_unlocks_html: " Odblokuje zakup: %{items}."
+      revoke_html: "%{name} straci zniżkę %{discount}%{unlocking}. Kupione wcześniej przedmioty zostają."
+      revoke_unlocking: " i możliwość zakupu: %{items}"
+
+    new:
+      page_title: "Przyznaj odznakę - %{name}"
+
+    form:
+      pick: "Przyznaj"
+      blank: "Wybierz odznakę"
+      title: "Przyznaj odznakę"
+      search: "Szukaj odznaki"
+      no_match: "Brak odznak o tej nazwie."
+      empty: "W tej grupie nie ma jeszcze odznak. Dodaj je w zakładce Odznaki, a potem wróć tutaj."
+      submit: "Wybierz odznakę"
+
+    confirm_destroy:
+      page_title: "Odbierz odznakę %{name}"
+      title: "Odebrać odznakę „%{name}”?"
+      revoke: "Odbierz odznakę"
diff --git a/config/locales/views/students_items.en.yml b/config/locales/views/students_items.en.yml
new file mode 100644
index 00000000..a310423b
--- /dev/null
+++ b/config/locales/views/students_items.en.yml
@@ -0,0 +1,28 @@
+en:
+  students_items:
+    helpers:
+      inventory_lead:
+        one: "%{count} item. Tell the teacher in class when you want to use an item."
+        other: "%{count} items. Tell the teacher in class when you want to use an item."
+      purchase_line: "Bought %{when}, for %{price}"
+      purchase_teacher_line: "Bought %{when}"
+      purchase_teacher_discount: "Bought %{when}, discounted from %{list}"
+      shop_line:
+        one: "You can afford %{count} item in the shop right now."
+        other: "You can afford %{count} items in the shop right now."
+
+    index:
+      own_title: "My items"
+      title: "Items — %{name}"
+      teacher_lead:
+        one: "%{count} item. The student settles using an item with you in class."
+        other: "%{count} items. The student settles using an item with you in class."
+      go_to_shop: "Go to the shop"
+      see_shop: "See the shop"
+      own_empty_title: "You don't have any items yet"
+      own_empty_body: "Collect currency in class and spend it in the shop — the items you buy will stay here with their purchase date."
+      empty_title: "The student hasn't bought anything yet"
+      empty_body: "Items will show up here with the price they paid and the purchase date."
+
+    card:
+      removed: "Removed from the shop"
diff --git a/config/locales/views/students_items.pl.yml b/config/locales/views/students_items.pl.yml
new file mode 100644
index 00000000..1f3f6150
--- /dev/null
+++ b/config/locales/views/students_items.pl.yml
@@ -0,0 +1,34 @@
+pl:
+  students_items:
+    helpers:
+      inventory_lead:
+        one: "%{count} przedmiot. Wykorzystanie przedmiotu zgłaszasz prowadzącemu na zajęciach."
+        few: "%{count} przedmioty. Wykorzystanie przedmiotu zgłaszasz prowadzącemu na zajęciach."
+        many: "%{count} przedmiotów. Wykorzystanie przedmiotu zgłaszasz prowadzącemu na zajęciach."
+        other: "%{count} przedmiotu. Wykorzystanie przedmiotu zgłaszasz prowadzącemu na zajęciach."
+      purchase_line: "Kupione %{when}, za %{price}"
+      purchase_teacher_line: "Kupione %{when}"
+      purchase_teacher_discount: "Kupione %{when}, ze zniżką z %{list}"
+      shop_line:
+        one: "Stać cię teraz na %{count} przedmiot w sklepie."
+        few: "Stać cię teraz na %{count} przedmioty w sklepie."
+        many: "Stać cię teraz na %{count} przedmiotów w sklepie."
+        other: "Stać cię teraz na %{count} przedmiotu w sklepie."
+
+    index:
+      own_title: "Moje przedmioty"
+      title: "Przedmioty — %{name}"
+      teacher_lead:
+        one: "%{count} przedmiot. Wykorzystanie przedmiotu student rozlicza z Tobą na zajęciach."
+        few: "%{count} przedmioty. Wykorzystanie przedmiotu student rozlicza z Tobą na zajęciach."
+        many: "%{count} przedmiotów. Wykorzystanie przedmiotu student rozlicza z Tobą na zajęciach."
+        other: "%{count} przedmiotu. Wykorzystanie przedmiotu student rozlicza z Tobą na zajęciach."
+      go_to_shop: "Przejdź do sklepu"
+      see_shop: "Zobacz sklep"
+      own_empty_title: "Nie masz jeszcze żadnego przedmiotu"
+      own_empty_body: "Zbieraj walutę na zajęciach i wydaj ją w sklepie — kupione przedmioty zostaną tutaj razem z datą zakupu."
+      empty_title: "Student nic jeszcze nie kupił"
+      empty_body: "Przedmioty pojawią się tu razem z ceną, jaką zapłacił, i datą zakupu."
+
+    card:
+      removed: "Usunięty z oferty"
diff --git a/config/locales/views/teachers.en.yml b/config/locales/views/teachers.en.yml
new file mode 100644
index 00000000..cd77f1f6
--- /dev/null
+++ b/config/locales/views/teachers.en.yml
@@ -0,0 +1,64 @@
+en:
+  teachers:
+    flash:
+      added: "Added: %{name}."
+      removed: "Removed from the group: %{name}."
+
+    helpers:
+      lead: "Assistant teachers help run this group."
+      lead_manage: "Only the owner can delete the group."
+      lead_read_only: "Only the group owner can add and remove teachers."
+      pool_hint:
+        one: "Type at least 2 characters of a name or e-mail. There is %{count} teacher at your university."
+        other: "Type at least 2 characters of a name or e-mail. There are %{count} teachers at your university."
+      candidate: "%{email}, %{university}"
+
+    index:
+      title: "Teachers"
+      add: "Add a teacher"
+      teacher: "Teacher"
+      role: "Role"
+      added: "Added"
+
+    row:
+      owner: "Owner"
+      created_group: "Created the group"
+      assistant: "Assistant teacher"
+      added: "Added"
+      remove_label: "Remove from the group: %{name}"
+
+    new:
+      page_title: "Add a teacher"
+
+    form:
+      title: "Add a teacher"
+      hint: "The teacher gets access to the group as soon as they're added."
+      placeholder: "Name or e-mail"
+      search: "Search for a teacher"
+      in_group: "Already in the group"
+      add_label: "Add %{name}"
+      overflow_hint: "Can't see the person? Type more letters or the e-mail."
+      no_results: "No results for"
+      no_results_hint: "Check the spelling or type the e-mail."
+      nobody: "Nobody to add: there are no other teacher accounts at your university yet."
+      # teacher_picker_controller.ts
+      js:
+        results:
+          one: "%{count} result"
+          other: "%{count} results"
+        overflow: ", showing the first %{max}"
+        query: "“%{query}”."
+
+    confirm_destroy:
+      page_title: "Remove %{name} from the group?"
+      title: "Remove %{name} from the group?"
+      body: "They'll lose access to the group. Rewards they awarded stay with the students."
+      remove: "Remove from group"
+
+  activerecord:
+    errors:
+      models:
+        story_group_teacher:
+          attributes:
+            user_id:
+              taken: "This person is already in the group."
diff --git a/config/locales/views/teachers.pl.yml b/config/locales/views/teachers.pl.yml
new file mode 100644
index 00000000..a3828d28
--- /dev/null
+++ b/config/locales/views/teachers.pl.yml
@@ -0,0 +1,68 @@
+pl:
+  teachers:
+    flash:
+      added: "Dodano: %{name}."
+      removed: "Usunięto z grupy: %{name}."
+
+    helpers:
+      lead: "Nauczyciele wspomagający pomagają prowadzić tę grupę."
+      lead_manage: "Grupę może usunąć tylko właściciel."
+      lead_read_only: "Dodawać i usuwać nauczycieli może tylko właściciel grupy."
+      pool_hint:
+        one: "Wpisz co najmniej 2 znaki imienia, nazwiska albo e-maila. W Twojej uczelni jest %{count} nauczyciel."
+        few: "Wpisz co najmniej 2 znaki imienia, nazwiska albo e-maila. W Twojej uczelni są %{count} nauczyciele."
+        many: "Wpisz co najmniej 2 znaki imienia, nazwiska albo e-maila. W Twojej uczelni jest %{count} nauczycieli."
+        other: "Wpisz co najmniej 2 znaki imienia, nazwiska albo e-maila. W Twojej uczelni jest %{count} nauczyciela."
+      candidate: "%{email}, %{university}"
+
+    index:
+      title: "Nauczyciele"
+      add: "Dodaj nauczyciela"
+      teacher: "Nauczyciel"
+      role: "Rola"
+      added: "Dodano"
+
+    row:
+      owner: "Właściciel"
+      created_group: "Utworzył grupę"
+      assistant: "Nauczyciel wspomagający"
+      added: "Dodano"
+      remove_label: "Usuń z grupy: %{name}"
+
+    new:
+      page_title: "Dodaj nauczyciela"
+
+    form:
+      title: "Dodaj nauczyciela"
+      hint: "Nauczyciel dostanie dostęp do grupy od razu po dodaniu."
+      placeholder: "Imię, nazwisko albo e-mail"
+      search: "Szukaj nauczyciela"
+      in_group: "Już w grupie"
+      add_label: "Dodaj %{name}"
+      overflow_hint: "Nie widzisz tej osoby? Wpisz więcej liter albo e-mail."
+      no_results: "Brak wyników dla"
+      no_results_hint: "Sprawdź pisownię albo wpisz e-mail."
+      nobody: "Nie ma kogo dodać: w Twojej uczelni nie ma jeszcze innych kont nauczycieli."
+      # teacher_picker_controller.ts
+      js:
+        results:
+          one: "%{count} wynik"
+          few: "%{count} wyniki"
+          many: "%{count} wyników"
+          other: "%{count} wyniku"
+        overflow: ", pokazujemy %{max} pierwszych"
+        query: "„%{query}”."
+
+    confirm_destroy:
+      page_title: "Usunąć %{name} z grupy?"
+      title: "Usunąć %{name} z grupy?"
+      body: "Straci dostęp do grupy. Nagrody, które przyznał, zostają u studentów."
+      remove: "Usuń z grupy"
+
+  activerecord:
+    errors:
+      models:
+        story_group_teacher:
+          attributes:
+            user_id:
+              taken: "Ta osoba jest już w grupie."
diff --git a/config/routes.rb b/config/routes.rb
index 17458dfa..5797c30a 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -3,6 +3,8 @@
 Rails.application.routes.draw do
   mount LetterOpenerWeb::Engine, at: '/letter_opener' if Rails.env.development?
 
+  resource :locale, only: :update
+
   resources :join, param: :code, only: %i[show new] do
     collection do
       post :create
diff --git a/test/controllers/locales_controller_test.rb b/test/controllers/locales_controller_test.rb
new file mode 100644
index 00000000..641c3046
--- /dev/null
+++ b/test/controllers/locales_controller_test.rb
@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class LocalesControllerTest < ActionDispatch::IntegrationTest
+  test 'renders in Polish by default' do
+    get login_path
+
+    assert_select 'html[lang=pl]'
+  end
+
+  test 'uses browser language when no locale was chosen' do
+    get login_path, headers: { 'Accept-Language' => 'en-US,en;q=0.9,pl;q=0.8' }
+
+    assert_select 'html[lang=en]'
+  end
+
+  test 'falls back to Polish for unsupported browser language' do
+    get login_path, headers: { 'Accept-Language' => 'de-DE,de;q=0.9' }
+
+    assert_select 'html[lang=pl]'
+  end
+
+  test 'switches locale and redirects back' do
+    patch locale_path, params: { locale: 'en' }, headers: { 'HTTP_REFERER' => login_url }
+
+    assert_redirected_to login_url
+    assert_equal 'en', cookies[:locale]
+
+    get login_path
+    assert_select 'html[lang=en]'
+  end
+
+  test 'chosen locale wins over browser language' do
+    patch locale_path, params: { locale: 'pl' }
+
+    get login_path, headers: { 'Accept-Language' => 'en-US,en;q=0.9' }
+    assert_select 'html[lang=pl]'
+  end
+
+  test 'ignores unsupported locale' do
+    patch locale_path, params: { locale: 'de' }
+
+    assert_redirected_to root_path
+    assert_nil cookies[:locale]
+  end
+
+  test 'logged in user can switch locale' do
+    sign_in FactoryBot.create(:user, :student)
+
+    patch locale_path, params: { locale: 'en' }, headers: { 'HTTP_REFERER' => home_url }
+
+    assert_redirected_to home_url
+    get home_path
+    assert_select 'html[lang=en]'
+  end
+end
diff --git a/test/controllers/students_badges_controller_test.rb b/test/controllers/students_badges_controller_test.rb
index 83425b8f..d570df56 100644
--- a/test/controllers/students_badges_controller_test.rb
+++ b/test/controllers/students_badges_controller_test.rb
@@ -39,4 +39,5 @@ class StudentsBadgesControllerTest < ActionDispatch::IntegrationTest
 
     assert_turbo_redirected_to story_group_student_url(@story_group, @story_group_student)
   end
+
 end
diff --git a/test/controllers/students_controller_test.rb b/test/controllers/students_controller_test.rb
index 74203898..939aadc4 100644
--- a/test/controllers/students_controller_test.rb
+++ b/test/controllers/students_controller_test.rb
@@ -44,4 +44,23 @@ class StudentsControllerTest < ActionDispatch::IntegrationTest
 
     assert_turbo_redirected_to story_group_students_url(@story_group)
   end
+
+  test 'lives notice uses Polish plural forms' do
+    @story_group_student.update!(lives: 1)
+
+    post update_lives_story_group_student_url(@story_group, @story_group_student, change: 1)
+    assert_equal "#{@story_group_student.display_name} ma teraz 2 życia.", flash[:notice]
+
+    @story_group_student.update!(lives: 4)
+    post update_lives_story_group_student_url(@story_group, @story_group_student, change: 1)
+    assert_equal "#{@story_group_student.display_name} ma teraz 5 żyć.", flash[:notice]
+  end
+
+  test 'lives notice in English' do
+    patch locale_path, params: { locale: 'en' }
+    @story_group_student.update!(lives: 0)
+
+    post update_lives_story_group_student_url(@story_group, @story_group_student, change: 1)
+    assert_equal "#{@story_group_student.display_name} now has 1 life.", flash[:notice]
+  end
 end
diff --git a/test/integration/translations_test.rb b/test/integration/translations_test.rb
new file mode 100644
index 00000000..d887a4ff
--- /dev/null
+++ b/test/integration/translations_test.rb
@@ -0,0 +1,535 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+# Opens every screen in both locales. raise_on_missing_translations is on in
+# test, so a missing key fails the render; on top of that an English page must
+# not contain Polish letters — a sign of wording that never went through I18n.
+class TranslationsTest < ActionDispatch::IntegrationTest
+  POLISH_LETTERS = /[ąćęłńóśźżĄĆĘŁŃÓŚŹŻ]/
+
+  setup do
+    @teacher = create(:user, :teacher, full_name: 'Anna Smith')
+    @group   = create(:story_group, owner: @teacher, name: 'Algorithms', currency_name: 'Coins',
+                                    ranking_enabled: true,)
+
+    @start_rank = create(:rank, story_group: @group, name: 'Novice', required_currency_value: 0, discount: 0)
+    @gold       = create(:rank, story_group: @group, name: 'Gold', required_currency_value: 50, discount: 10)
+    @badge      = create(:badge, story_group: @group, name: 'Helper', discount: 5)
+    @badge2     = create(:badge, story_group: @group, name: 'Speaker', discount: 7)
+
+    @item = create(:item, story_group: @group, name: 'Retake', price: 40, unlock_rank: @gold,
+                          min_rank_for_discount: @start_rank,)
+    @item.unlock_badges << @badge
+    @item.discount_badges << @badge2
+    @cheap = create(:item, story_group: @group, name: 'Hint', price: 1, can_buy_at_0_lives: true)
+
+    @invite   = create(:story_group_invite, story_group: @group)
+    @template = create(:activity_group_template, story_group: @group, base_name: 'Lab')
+    create(:activity_group_template_category, activity_group_template: @template)
+    @sheet    = create(:activity_group, story_group: @group, activity_group_template: @template, name: 'Lab 1')
+    @category = create(:activity_group_category, activity_group: @sheet)
+    @attendance = create(:activity_group_category, activity_group: @sheet, didactic_description: 'Attendance',
+                                                   position:       1,)
+
+    @assistant  = create(:user, :teacher, full_name: 'Bob Brown')
+    @assistance = create(:story_group_teacher, story_group: @group, user: @assistant)
+
+    @student    = create(:user, :student, full_name: 'Carl Green')
+    @membership = create(:story_group_student, story_group: @group, user: @student, nickname: 'Comet',
+                                               lives: 2, current_currency: 30, total_currency: 30,)
+    create(:students_activity_group_category, student: @membership, activity_group_category: @category)
+    @awarded = create(:students_badge, story_group_student: @membership, badge: @badge)
+    create(:students_item, story_group_student: @membership, item: @cheap, price_paid: 1)
+    create(:currency_transaction, student: @membership, amount: 10, kind: :reward,
+                                  transactionable: @category,)
+    create(:currency_transaction, student: @membership, amount: -1, kind: :purchase, transactionable: @cheap)
+    CurrencyAdjusterService.new(student: @membership, granted_by_user: @teacher).adjust(3)
+    create(:notification, user: @teacher, story_group: @group, story_group_student: @membership, item: @cheap)
+
+    @other_group  = create(:story_group, owner: @teacher, name: 'Databases', currency_name: 'Gems')
+    @other_invite = create(:story_group_invite, story_group: @other_group)
+  end
+
+  %w[pl en].each do |locale|
+    test "teacher screens render in #{locale}" do
+      choose(locale)
+      sign_in @teacher
+
+      visit_all(locale, teacher_paths)
+    end
+
+    test "student screens render in #{locale}" do
+      choose(locale)
+      sign_in @student
+
+      visit_all(locale, student_paths)
+    end
+
+    test "logged-out screens render in #{locale}" do
+      choose(locale)
+
+      visit_all(locale, [login_path, new_auth_passwordless_path])
+
+      post auth_passwordless_path, params: { email: 'nobody@example.com' }
+      visit_all(locale, [auth_passwordless_inbox_path])
+    end
+
+    test "the login e-mail is written in #{locale}" do
+      mail = I18n.with_locale(locale) do
+        PasswordlessMailer.with(token_link: 'https://example.com/t', email: @student.email,
+                                user_name: @student.full_name,).token_email.message
+      end
+
+      assert_equal I18n.t('passwordless_mailer.token_email.subject', locale: locale), mail.subject
+      assert_no_polish(mail.body.encoded, 'login e-mail') if locale == 'en'
+    end
+
+    # The tests below submit forms: a success must leave a translated notice
+    # (checked as a string and again on the page it lands on), a rejected form
+    # must re-render with translated validation messages.
+    test "group settings forms answer in #{locale}" do
+      choose(locale)
+      sign_in @teacher
+
+      patch story_group_path(@group), params: { story_group: { name: 'Algorithms II' } }
+      assert_flash_shown(locale)
+      patch story_group_path(@group), params: { story_group: { name: '' } }
+      assert_form_rejected(locale)
+      post story_groups_path, params: { story_group: { name: '' }, setup: { path: 'custom' } }
+      assert_form_rejected(locale)
+
+      patch story_group_ranking_path(@group), params: { story_group: { ranking_enabled: '1', ranking_mode: 'full' } }
+      assert_flash_shown(locale)
+      patch story_group_ranking_path(@group), params: { story_group: { ranking_enabled: '0' } }
+      assert_flash_shown(locale)
+
+      post story_group_teachers_path(@group),
+           params: { story_group_teacher: { user_id: create(:user, :teacher, full_name: 'Dana White').id } }
+      assert_flash_shown(locale)
+      delete story_group_teacher_path(@group, @assistance)
+      assert_flash_shown(locale)
+
+      post story_group_invites_path(@group),
+           params: { story_group_invite: { limit_enabled: '1', max_uses: '10' } }
+      assert_flash_shown(locale)
+      post story_group_invites_path(@group),
+           params: { story_group_invite: { expiry_enabled: '1', expires_on: '2000-01-01' } }
+      assert_form_rejected(locale)
+      patch story_group_invite_path(@group, @invite), params: { story_group_invite: { limit_enabled: '0' } }
+      assert_flash_shown(locale)
+      delete story_group_invite_path(@group, @invite)
+      assert_flash_shown(locale)
+
+      delete story_group_path(@group), params: { confirm: 'wrong name' }
+      assert_form_rejected(locale)
+      delete story_group_path(@group), params: { confirm: @group.reload.name }
+      assert_flash_shown(locale)
+    end
+
+    test "rank, badge and item forms answer in #{locale}" do
+      choose(locale)
+      sign_in @teacher
+
+      post story_group_ranks_path(@group), params: { rank: rank_params(name: 'Silver', required_currency_value: 20) }
+      assert_flash_shown(locale)
+      post story_group_ranks_path(@group), params: { rank: rank_params(name: 'Copy', required_currency_value: 50) }
+      assert_form_rejected(locale)
+      patch story_group_rank_path(@group, @gold), params: { rank: { name: 'Platinum' } }
+      assert_flash_shown(locale)
+      delete story_group_rank_path(@group, @gold) # Retake unlocks at this rank, so it is blocked
+      assert_flash_shown(locale)
+
+      post story_group_badges_path(@group), params: { badge: badge_params(name: 'Mentor') }
+      assert_flash_shown(locale)
+      post story_group_badges_path(@group), params: { badge: badge_params(name: '') }
+      assert_form_rejected(locale)
+      patch story_group_badge_path(@group, @badge), params: { badge: { name: 'Big helper' } }
+      assert_flash_shown(locale)
+      delete story_group_badge_path(@group, @badge2)
+      assert_flash_shown(locale)
+
+      post story_group_items_path(@group), params: { item: item_params(name: 'Pass') }
+      assert_flash_shown(locale)
+      post story_group_items_path(@group), params: { item: item_params(name: '', price: -1) }
+      assert_form_rejected(locale)
+      patch story_group_item_path(@group, @item), params: { item: { name: 'Second try' } }
+      assert_flash_shown(locale)
+      delete story_group_item_path(@group, @item)
+      assert_flash_shown(locale)
+    end
+
+    test "sheet and grading forms answer in #{locale}" do
+      choose(locale)
+      sign_in @teacher
+
+      post story_group_activity_group_templates_path(@group), params: {
+        activity_group_template: {
+          base_name:             'Quiz',
+          categories_attributes: { '0' => { didactic_description: 'Score', reward: 5, position: 0 } },
+        },
+      }
+      assert_flash_shown(locale)
+      post story_group_activity_group_templates_path(@group),
+           params: { activity_group_template: { base_name: 'Empty' } }
+      assert_form_rejected(locale)
+      patch story_group_activity_group_template_path(@group, @template),
+            params: { activity_group_template: { base_name: 'Lab+' } }
+      assert_flash_shown(locale)
+
+      post story_group_activity_groups_path(@group),
+           params: { activity_group: { activity_group_template_id: @template.id, mode: 'single', name: 'Lab 2' } }
+      assert_flash_shown(locale)
+      post story_group_activity_groups_path(@group, count: 3),
+           params: { activity_group: { activity_group_template_id: @template.id, mode: 'many' } }
+      assert_flash_shown(locale)
+
+      grading = story_group_activity_group_students_activity_group_categories_path(@group, @sheet)
+      patch grading
+      assert_flash_shown(locale)
+      patch grading, params: { completions: { @membership.id => { @attendance.id => '1' } } }
+      assert_flash_shown(locale)
+
+      delete story_group_activity_group_path(@group, @sheet)
+      assert_flash_shown(locale)
+      delete story_group_activity_group_template_path(@group, @template)
+      assert_flash_shown(locale)
+    end
+
+    test "actions on a student answer in #{locale}" do
+      choose(locale)
+      sign_in @teacher
+      student = story_group_student_path(@group, @membership)
+
+      patch student, params: { story_group_student: { lives: 3 } }
+      assert_flash_shown(locale)
+      patch student, params: { story_group_student: { lives: -1 } }
+      assert_form_rejected(locale)
+      post update_lives_story_group_student_path(@group, @membership), params: { change: -1 }
+      assert_flash_shown(locale)
+      patch student, params: { story_group_student: { lives: 0 } }
+      post update_lives_story_group_student_path(@group, @membership), params: { change: -1 }
+      assert_flash_shown(locale)
+
+      adjustment = story_group_student_currency_adjustment_path(@group, @membership)
+      post adjustment, params: { currency_adjustment: { sign: '1', amount: '5' } }
+      assert_flash_shown(locale)
+      post adjustment, params: { currency_adjustment: { sign: '1', amount: '' } }
+      assert_form_rejected(locale)
+      post adjustment, params: { currency_adjustment: { sign: '-1', amount: '9999' } }
+      assert_form_rejected(locale)
+
+      post story_group_student_badges_path(@group, @membership), params: { students_badge: { badge_id: @badge2.id } }
+      assert_flash_shown(locale)
+      post story_group_student_badges_path(@group, @membership), params: { students_badge: { badge_id: @badge2.id } }
+      assert_form_rejected(locale)
+      delete story_group_student_badge_path(@group, @membership, @awarded)
+      assert_flash_shown(locale)
+
+      delete student
+      assert_flash_shown(locale)
+    end
+
+    test "student actions answer in #{locale}" do
+      choose(locale)
+      sign_in @student
+
+      post buy_story_group_shop_path(@group, @cheap)
+      assert_flash_shown(locale)
+      post buy_story_group_shop_path(@group, @item) # locked behind the Gold rank and a badge
+      assert_flash_shown(locale)
+
+      patch story_group_membership_path(@group), params: { story_group_student: { nickname: 'Rocket' } }
+      assert_flash_shown(locale)
+      patch story_group_membership_path(@group), params: { story_group_student: { nickname: 'x' * 200 } }
+      assert_form_rejected(locale)
+
+      post join_index_path, params: { code: 'NOPE00' }
+      assert_form_rejected(locale)
+      post join_index_path, params: { code: @other_invite.code }
+      follow_redirect!
+      assert_response :success
+      assert_translated(locale, response.body, 'join done')
+
+      delete story_group_membership_path(@group)
+      assert_flash_shown(locale)
+    end
+
+    test "sign-in and access alerts are in #{locale}" do
+      choose(locale)
+
+      get home_path
+      assert_flash_shown(locale)
+      get auth_passwordless_verify_path(token: 'bogus')
+      assert_flash_shown(locale)
+      post auth_passwordless_path, params: { email: @teacher.email }
+      post auth_passwordless_path, params: { email: @teacher.email } # only a resend leaves a notice
+      assert_flash_shown(locale)
+
+      sign_in @teacher
+      get login_path
+      assert_flash_shown(locale)
+      get story_group_path(id: 0)
+      assert_flash_shown(locale)
+    end
+
+    test "global admin screens render in #{locale}" do
+      choose(locale)
+      sign_in create(:user, :global_admin)
+      org, org_admin, = organization_with_people
+
+      visit_all(locale, [
+                  home_path,
+                  organizations_path,
+                  organization_path(org),
+                  new_organization_path,
+                  edit_organization_path(org),
+                  confirm_destroy_organization_path(org),
+                  new_admin_organization_path(org),
+                  confirm_destroy_organization_admin_path(org, org_admin),
+                ],)
+    end
+
+    test "organization admin screens render in #{locale}" do
+      choose(locale)
+      org, org_admin, member = organization_with_people
+      org_admin.update!(first_login: false) # an invited admin is sent to account setup first
+      sign_in org_admin
+
+      visit_all(locale, [
+                  home_path,
+                  organization_path(org),
+                  new_user_organization_path(org),
+                  edit_organization_user_path(org, member),
+                  confirm_destroy_organization_user_path(org, member),
+                ],)
+    end
+
+    test "organization forms answer in #{locale}" do
+      choose(locale)
+      sign_in create(:user, :global_admin)
+      org, org_admin, member = organization_with_people
+
+      post organizations_path, params: { organization: { name: org.name, max_members: 5 } } # names are unique
+      assert_form_rejected(locale)
+      post organizations_path, params: { organization: { name: 'Polytechnic', max_members: 5 } }
+      assert_flash_shown(locale)
+      patch organization_path(org), params: { organization: { max_members: 1 } } # below the 3 accounts
+      assert_form_rejected(locale)
+      patch organization_path(org), params: { organization: { max_members: 10 } }
+      assert_flash_shown(locale)
+
+      post add_admin_organization_path(org), params: { user: { email: 'new.admin@example.com' } }
+      assert_flash_shown(locale)
+      post add_admin_organization_path(org), params: { user: { email: '' } }
+      assert_form_rejected(locale)
+      delete organization_admin_path(org, org_admin)
+      assert_flash_shown(locale)
+
+      sign_in create(:user, :organization_admin, organization: org.reload)
+      post add_user_organization_path(org), params: {
+        user: {
+          email:     'new.user@example.com',
+          full_name: 'Eve Black',
+          role:      'student',
+        },
+      }
+      assert_flash_shown(locale)
+      post add_user_organization_path(org), params: { user: { email: '', full_name: '', role: 'student' } }
+      assert_form_rejected(locale)
+      patch organization_user_path(org, member), params: { user: { full_name: 'Fred Gray' } }
+      assert_flash_shown(locale)
+      delete organization_user_path(org, member)
+      assert_flash_shown(locale)
+
+      sign_in create(:user, :global_admin)
+      delete organization_path(org), params: { confirm: 'wrong' }
+      assert_form_rejected(locale)
+      delete organization_path(org), params: { confirm: org.name }
+      assert_flash_shown(locale)
+    end
+
+    test "account setup answers in #{locale}" do
+      choose(locale)
+      sign_in create(:user, :organization_admin, first_login: true, full_name: nil, organization: create(:organization))
+
+      visit_all(locale, [edit_account_setup_path])
+      patch account_setup_path, params: { user: { full_name: '' } }
+      assert_form_rejected(locale)
+      patch account_setup_path, params: { user: { full_name: 'Grace Hall' } }
+      assert_flash_shown(locale)
+    end
+
+    test "the invitation e-mail is written in #{locale}" do
+      mail = I18n.with_locale(locale) do
+        InvitationMailer.with(token_link: 'https://example.com/t', email: 'a@example.com',
+                              organization_name: 'Polytechnic', role: :admin,).invitation_email.message
+      end
+
+      assert_equal I18n.t('invitation_mailer.invitation_email.subject', locale: locale), mail.subject
+      mail.parts.each { |part| assert_no_polish(part.body.decoded, 'invitation e-mail') } if locale == 'en'
+    end
+  end
+
+  test 'a quick-start group is created in the teacher’s language' do
+    choose('en')
+    sign_in @teacher
+
+    post story_groups_path, params: {
+      story_group: { name: 'Physics', currency_name: 'Stars', default_lives: 3 },
+      setup:       { path: 'quick', pack: 'scifi', classes: 12 },
+    }
+
+    group = StoryGroup.find_by!(name: 'Physics')
+    assert_equal %w[Cadet Pilot Navigator Commander Admiral], group.ranks.by_threshold.map(&:name)
+    assert_equal 'Classes', group.activity_group_templates.first.base_name
+  end
+
+  private
+
+  def choose(locale)
+    patch locale_path, params: { locale: locale }
+  end
+
+  def visit_all(locale, paths)
+    paths.each do |path|
+      get path
+      assert_response :success, "#{path} (#{locale})"
+      assert_select "html[lang=#{locale}]" if response.body.include?('<html')
+      assert_no_polish(response.body, path) if locale == 'en'
+    end
+  end
+
+  # The page after a form action: a plain redirect, or the turbo-stream
+  # "redirect" action that redirect_outside_turbo_frame renders.
+  def assert_flash_shown(locale)
+    where   = "#{request.request_method} #{request.path}"
+    message = flash[:notice] || flash[:alert]
+    assert message.present?, "no flash after #{where}"
+    assert_translated(locale, message, where)
+
+    target = response.redirect? ? response.location : response.body[/action="redirect"[^>]*target="([^"]+)"/, 1]
+    flunk "no redirect after #{where}" unless target
+    get target
+    follow_redirect! while response.redirect?
+    assert_response :success, "page after #{where}"
+    assert_translated(locale, response.body, "page after #{where}")
+  end
+
+  def assert_form_rejected(locale)
+    where = "#{request.request_method} #{request.path}"
+    assert_response :unprocessable_content, where
+    assert_translated(locale, response.body, where)
+  end
+
+  def assert_translated(locale, html, where)
+    assert_no_match(/translation missing/i, html, "missing translation in #{where}")
+    assert_no_polish(html, where) if locale == 'en'
+  end
+
+  # An organization with an invited administrator and a student, so the
+  # lists, the "invitation sent" markers and the capacity text all render.
+  def organization_with_people
+    org      = create(:organization, max_members: 3)
+    admin    = create(:user, :organization_admin, organization: org, first_login: true)
+    member   = create(:user, :student, organization: org, first_login: true)
+    create(:story_group, owner: create(:user, :teacher, organization: org))
+
+    [org, admin, member]
+  end
+
+  def rank_params(**attrs)
+    { discount: 5, icon_glyph: 'chev1' }.merge(attrs)
+  end
+
+  def badge_params(**attrs)
+    { didactic_description: 'Helps others', discount: 3, icon_glyph: 'rabbit' }.merge(attrs)
+  end
+
+  def item_params(**attrs)
+    { didactic_description: 'Skip one task', price: 5, icon_glyph: 'shield' }.merge(attrs)
+  end
+
+  def assert_no_polish(html, where)
+    text  = Nokogiri::HTML(html).text
+    match = text.match(POLISH_LETTERS)
+    return pass unless match
+
+    snippet = text[[match.begin(0) - 40, 0].max, 80].squish
+    flunk "Polish text left in #{where}: …#{snippet}…"
+  end
+
+  def teacher_paths
+    [
+      home_path,
+      story_groups_path,
+      new_story_group_path,
+      preset_preview_story_groups_path(pack: 'fantasy', classes: 12, currency_name: 'Coins'),
+      story_group_path(@group),
+      edit_story_group_path(@group),
+      confirm_destroy_story_group_path(@group),
+      created_story_group_path(@group),
+      story_group_students_path(@group),
+      *StudentSheet::TABS.map { |tab| story_group_student_path(@group, @membership, tab: tab) },
+      edit_story_group_student_path(@group, @membership),
+      confirm_destroy_story_group_student_path(@group, @membership),
+      story_group_student_students_items_path(@group, @membership),
+      new_story_group_student_badge_path(@group, @membership),
+      confirm_destroy_story_group_student_badge_path(@group, @membership, @awarded),
+      new_story_group_student_currency_adjustment_path(@group, @membership),
+      story_group_items_path(@group),
+      new_story_group_item_path(@group),
+      edit_story_group_item_path(@group, @item),
+      confirm_destroy_story_group_item_path(@group, @item),
+      story_group_ranks_path(@group),
+      new_story_group_rank_path(@group),
+      edit_story_group_rank_path(@group, @gold),
+      confirm_destroy_story_group_rank_path(@group, @gold),
+      story_group_badges_path(@group),
+      new_story_group_badge_path(@group),
+      edit_story_group_badge_path(@group, @badge),
+      confirm_destroy_story_group_badge_path(@group, @badge),
+      story_group_invites_path(@group),
+      new_story_group_invite_path(@group),
+      edit_story_group_invite_path(@group, @invite),
+      story_group_invite_path(@group, @invite),
+      quick_story_group_invites_path(@group),
+      confirm_destroy_story_group_invite_path(@group, @invite),
+      story_group_teachers_path(@group),
+      new_story_group_teacher_path(@group),
+      confirm_destroy_story_group_teacher_path(@group, @assistance),
+      story_group_activity_groups_path(@group),
+      new_story_group_activity_group_path(@group, template_id: @template.id),
+      edit_story_group_activity_group_path(@group, @sheet),
+      confirm_destroy_story_group_activity_group_path(@group, @sheet),
+      new_story_group_activity_group_template_path(@group),
+      edit_story_group_activity_group_template_path(@group, @template),
+      confirm_destroy_story_group_activity_group_template_path(@group, @template),
+      edit_story_group_activity_group_students_activity_group_categories_path(@group, @sheet),
+      story_group_ranking_path(@group),
+      confirm_visibility_story_group_ranking_path(@group, enabled: false),
+      confirm_mode_story_group_ranking_path(@group, mode: 'full'),
+      notifications_path,
+    ]
+  end
+
+  def student_paths
+    [
+      home_path,
+      story_groups_path,
+      story_group_path(@group),
+      story_group_shop_index_path(@group),
+      confirm_buy_story_group_shop_path(@group, @cheap),
+      story_group_student_students_items_path(@group, @membership),
+      story_group_student_currency_transactions_path(@group, @membership),
+      story_group_badges_path(@group),
+      story_group_ranks_path(@group),
+      story_group_ranking_path(@group),
+      edit_story_group_membership_path(@group),
+      nickname_story_group_membership_path(@group),
+      confirm_leave_story_group_membership_path(@group),
+      new_join_path,
+      join_path(code: @other_invite.code),
+    ]
+  end
+end
diff --git a/test/models/item_test.rb b/test/models/item_test.rb
index 9ffb23b1..d8c5009f 100644
--- a/test/models/item_test.rb
+++ b/test/models/item_test.rb
@@ -140,4 +140,13 @@ class ItemTest < ActiveSupport::TestCase
 
     assert_equal %w[Tani Drogi Item], @story_group.items.by_price.pluck(:name)
   end
+
+  test 'destroying an item takes its purchase notifications with it' do
+    notification = FactoryBot.create(:notification, story_group: @story_group, story_group_student: @student,
+                                                    item:        @item,)
+
+    @item.destroy!
+
+    assert_not Notification.exists?(notification.id)
+  end
 end
diff --git a/test/models/organization_test.rb b/test/models/organization_test.rb
index e314cd99..a41ecf83 100644
--- a/test/models/organization_test.rb
+++ b/test/models/organization_test.rb
@@ -30,7 +30,7 @@ class OrganizationTest < ActiveSupport::TestCase
 
     organization.max_members = 1
     assert_not organization.valid?
-    assert_includes organization.errors[:max_members], "can't be lower than the current number of members (2)"
+    assert organization.errors.added?(:max_members, :below_members, count: 2)
   end
 
   test 'requires unique name' do
diff --git a/test/models/story_group_student_test.rb b/test/models/story_group_student_test.rb
index e337aa34..63c46dac 100644
--- a/test/models/story_group_student_test.rb
+++ b/test/models/story_group_student_test.rb
@@ -3,7 +3,6 @@
 require 'test_helper'
 
 class StoryGroupStudentTest < ActiveSupport::TestCase
-
   setup do
     @owner = ::FactoryBot.create(:user)
     @student_user = ::FactoryBot.create(:user)
@@ -60,16 +59,14 @@ class StoryGroupStudentTest < ActiveSupport::TestCase
     assert_nil student.next_rank
   end
 
-  test 'removing a student who bought something clears their purchase notifications' do
-    story_group = FactoryBot.create(:story_group)
-    student = FactoryBot.create(:story_group_student, story_group: story_group,
-                                                      user:        FactoryBot.create(:user, :student),)
-    item = FactoryBot.create(:item, story_group: story_group)
-    FactoryBot.create(:notification, user: story_group.owner, story_group: story_group,
-                                     story_group_student: student, item: item,)
-
-    assert_difference 'Notification.count', -1 do
-      student.destroy!
-    end
+  test 'a student who bought something can still be removed, with the purchase notifications' do
+    group        = StoryGroup.create!(name: 'Shop Group', currency_name: 'Gold', owner: @owner)
+    student      = StoryGroupStudent.create!(user: @student_user, story_group: group)
+    notification = ::FactoryBot.create(:notification, user: @owner, story_group: group, story_group_student: student,
+                                                      item: ::FactoryBot.create(:item, story_group: group),)
+
+    student.destroy!
+
+    assert_not Notification.exists?(notification.id)
   end
 end
diff --git a/test/models/story_group_test.rb b/test/models/story_group_test.rb
index 73edc248..69eb7240 100644
--- a/test/models/story_group_test.rb
+++ b/test/models/story_group_test.rb
@@ -12,4 +12,16 @@ class StoryGroupTest < ActiveSupport::TestCase
     assert_equal true, story_group.invalid?
     assert_equal true, story_group.errors[:name].any?
   end
+
+  test 'a group with purchases can be destroyed, notifications included' do
+    story_group = FactoryBot.create(:story_group)
+    student     = FactoryBot.create(:story_group_student, story_group: story_group, user: FactoryBot.create(:user))
+    item        = FactoryBot.create(:item, story_group: story_group)
+    notification = FactoryBot.create(:notification, story_group: story_group, story_group_student: student,
+                                                    item:        item,)
+
+    story_group.destroy!
+
+    assert_not Notification.exists?(notification.id)
+  end
 end
diff --git a/test/models/user_test.rb b/test/models/user_test.rb
index d2ddf890..4a262bb1 100644
--- a/test/models/user_test.rb
+++ b/test/models/user_test.rb
@@ -16,7 +16,7 @@ class UserTest < ActiveSupport::TestCase
 
     user = FactoryBot.build(:user, organization: organization)
     assert_not user.valid?
-    assert_includes user.errors[:organization], 'has reached its member limit'
+    assert user.errors.added?(:organization, :member_limit)
   end
 
   test 'existing member can be updated in a full organization' do
diff --git a/test/services/dashboard/teacher_test.rb b/test/services/dashboard/teacher_test.rb
index 0ee04683..576289c2 100644
--- a/test/services/dashboard/teacher_test.rb
+++ b/test/services/dashboard/teacher_test.rb
@@ -4,6 +4,9 @@
 
 class Dashboard::TeacherTest < ActiveSupport::TestCase
   setup do
+    # Purchases are bucketed by calendar day, so "1.hour.ago" must not cross
+    # midnight — pin the clock to midday. travel_back runs after each test.
+    travel_to Time.current.noon
     @teacher = FactoryBot.create(:user, role: :teacher)
   end
 
@@ -30,9 +33,9 @@ class Dashboard::TeacherTest < ActiveSupport::TestCase
 
     dashboard = Dashboard::Teacher.new(user: @teacher).load
 
-    assert_equal 1, dashboard.purchases_on('Dziś').size
-    assert_equal 1, dashboard.purchases_on('Wczoraj').size
-    assert_equal 1, dashboard.purchases_on('Wcześniej').size
+    assert_equal 1, dashboard.purchases_on(:today).size
+    assert_equal 1, dashboard.purchases_on(:yesterday).size
+    assert_equal 1, dashboard.purchases_on(:earlier).size
     assert_equal 2, dashboard.recent_purchases.size
     assert_equal 1, dashboard.recent_group_count
   end
diff --git a/test/services/starter_pack_builder_test.rb b/test/services/starter_pack_builder_test.rb
index 9518abb0..2a3cf4c0 100644
--- a/test/services/starter_pack_builder_test.rb
+++ b/test/services/starter_pack_builder_test.rb
@@ -20,7 +20,7 @@ def build(pack: 'neutral', classes: 12, selection: {})
     assert_equal 7, @story_group.items.count
     assert_equal 1, @story_group.activity_group_templates.count
     assert_equal 8, @story_group.activity_group_templates.first.categories.count
-    assert_equal StarterPack::TEMPLATE_NAME,
+    assert_equal StarterPack.template_name,
                  @story_group.activity_group_templates.first.base_name
     assert_equal 5, result.ranks.size
   end
@@ -34,7 +34,7 @@ def build(pack: 'neutral', classes: 12, selection: {})
   test 'categories keep the preset order' do
     build
 
-    assert_equal StarterPack::CATEGORIES.map(&:first),
+    assert_equal StarterPack.category_names,
                  @story_group.activity_group_templates.first.categories.map(&:didactic_description)
   end