diff --git a/README.md b/README.md
index 0963b09..eeb1118 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,14 @@
 # Lecture Attendance Management System
+
+## Alterations
+
+### Continuum Mechanics
+
+```ruby
+continuum_mechanics = Course.find(nil)
+
+continuum_mechanics.import_from_calendar!
+continuum_mechanics.lectures.filter { |lecture| lecture.start_time.monday? }.map {|lecture| lecture.update!(kind: Lecture.kinds[:problems_class]) }
+continuum_mechanics.lectures.find_by(start_time: '2023-10-02 08:15:00.000000').destroy!
+continuum_mechanics.renumber_lectures!
+```
diff --git a/app/assets/stylesheets/application.tailwind.css b/app/assets/stylesheets/application.tailwind.css
index 8666d2f..c6f38c5 100644
--- a/app/assets/stylesheets/application.tailwind.css
+++ b/app/assets/stylesheets/application.tailwind.css
@@ -2,6 +2,10 @@
 @tailwind components;
 @tailwind utilities;
 
+.action-button {
+    @apply rounded bg-indigo-600 px-2 py-1 font-semibold text-white shadow-sm hover:bg-indigo-500 focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-indigo-600;
+}
+
 /*
 
 @layer components {
diff --git a/app/controllers/lecture_controller.rb b/app/controllers/lecture_controller.rb
new file mode 100644
index 0000000..45ad7cf
--- /dev/null
+++ b/app/controllers/lecture_controller.rb
@@ -0,0 +1,14 @@
+class LectureController < ApplicationController
+  def start
+    lecture = Lecture.find(params[:id])
+
+    Toggl::start_time_entry(
+      description: lecture.title,
+      project_id: lecture.course.toggl_project,
+    )
+
+    if lecture.recording.present?
+      redirect_to lecture.recording.recording_url, allow_other_host: true
+    end
+  end
+end
diff --git a/app/helpers/lecture_helper.rb b/app/helpers/lecture_helper.rb
new file mode 100644
index 0000000..397536c
--- /dev/null
+++ b/app/helpers/lecture_helper.rb
@@ -0,0 +1,2 @@
+module LectureHelper
+end
diff --git a/app/lib/toggl.rb b/app/lib/toggl.rb
index b991db4..7f43956 100644
--- a/app/lib/toggl.rb
+++ b/app/lib/toggl.rb
@@ -10,4 +10,17 @@ module Toggl
       headers: { 'Content-Type' => 'application/json', 'Accept' => 'application/json' }
     ).body)
   end
+
+  def self.start_time_entry(description:, project_id:)
+    HTTParty.post(
+      "http://localhost:3005/start_time_entry",
+      body: {
+        "created_with": "Attendance Tracker",
+        "description": description,
+        "duration": -1,
+        "project_id": project_id,
+      }.to_json,
+      headers: { 'Content-Type' => 'application/json', 'Accept' => 'application/json' }
+    )
+  end
 end
diff --git a/app/models/course.rb b/app/models/course.rb
index fb41db0..0faf14d 100644
--- a/app/models/course.rb
+++ b/app/models/course.rb
@@ -61,6 +61,7 @@ class Course < ApplicationRecord
     end
   end
 
+  # What should this do for existing attendances?
   def renumber_lectures!
     lectures.group_by(&:kind).each do |kind, lectures|
       lectures.sort_by(&:start_time).each_with_index do |lecture, index|
diff --git a/app/models/lecture.rb b/app/models/lecture.rb
index b87cfbb..e31b27d 100644
--- a/app/models/lecture.rb
+++ b/app/models/lecture.rb
@@ -5,7 +5,7 @@ class Lecture < ApplicationRecord
 
   enum :kind, [
     :lecture,
-    :problem_class,
+    :problems_class,
   ], default: :lecture
 
   def week_number
diff --git a/app/views/attendance_tracker/index.html.erb b/app/views/attendance_tracker/index.html.erb
index 9ebbdd4..024d4a3 100644
--- a/app/views/attendance_tracker/index.html.erb
+++ b/app/views/attendance_tracker/index.html.erb
@@ -66,11 +66,14 @@
 
                       <td class="whitespace-nowrap px-3 py-4 text-sm text-gray-500">
                         <% if lecture.attendance.nil? %>
-                          <button type="button" class="rounded bg-indigo-600 px-2 py-1 font-semibold text-white shadow-sm hover:bg-indigo-500 focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-indigo-600">
-                            Start
-                          </button>
+                          <%= button_to "Start",
+                                        lectures_start_path(id: lecture.id),
+                                        class: 'action-button'
+                          %>
                         <% else %>
-                          <%= link_to "Open recording", lecture.recording&.recording_url %>
+                          <% if lecture.recording %>
+                            <%= link_to "Open recording", lecture.recording&.recording_url %>
+                          <% end %>
                         <% end %>
                       </td>
                     <% end %>
diff --git a/app/views/lecture/start.html.erb b/app/views/lecture/start.html.erb
new file mode 100644
index 0000000..914aa7d
--- /dev/null
+++ b/app/views/lecture/start.html.erb
@@ -0,0 +1,4 @@
+<div>
+  <h1 class="font-bold text-4xl">Lecture#start</h1>
+  <p>Find me in app/views/lecture/start.html.erb</p>
+</div>
diff --git a/config/routes.rb b/config/routes.rb
index 997198e..bd11a95 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -9,4 +9,6 @@ Rails.application.routes.draw do
   end
 
   root controller: :attendance_tracker, action: :index
+
+  post '/lectures/:id/start', to: 'lecture#start', as: :lectures_start
 end
diff --git a/test/controllers/lecture_controller_test.rb b/test/controllers/lecture_controller_test.rb
new file mode 100644
index 0000000..626b833
--- /dev/null
+++ b/test/controllers/lecture_controller_test.rb
@@ -0,0 +1,8 @@
+require "test_helper"
+
+class LectureControllerTest < ActionDispatch::IntegrationTest
+  test "should get start" do
+    get lecture_start_url
+    assert_response :success
+  end
+end