diff --git a/app/controllers/groups_controller.rb b/app/controllers/groups_controller.rb
--- a/app/controllers/groups_controller.rb
+++ b/app/controllers/groups_controller.rb
@@ -2,6 +2,7 @@
   before_action :set_group, only: [:show, :edit, :update, :destroy,
                                    :add_user, :remove_user,:remove_all_user,
                                    :add_problem, :remove_problem,:remove_all_problem,
+                                   :toggle,
                                   ]
   before_action :admin_authorization
 
@@ -49,6 +50,11 @@
     redirect_to groups_url, notice: 'Group was successfully destroyed.'
   end
 
+  def toggle
+    @group.enabled = @group.enabled? ? false : true
+    @group.save
+  end
+
   def remove_user
     user = User.find(params[:user_id])
     @group.users.delete(user)
@@ -99,6 +105,6 @@
 
     # Only allow a trusted parameter "white list" through.
     def group_params
-      params.require(:group).permit(:name, :description)
+      params.require(:group).permit(:name, :description, :enabled)
     end
 end
diff --git a/app/controllers/main_controller.rb b/app/controllers/main_controller.rb
--- a/app/controllers/main_controller.rb
+++ b/app/controllers/main_controller.rb
@@ -188,7 +188,7 @@
       @user = user
     end
   end
-  
+
   protected
 
   def prepare_announcements(recent=nil)
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -113,8 +113,9 @@
 
   def toggle_button(on,toggle_url,id, option={})
     btn_size = option[:size] || 'btn-xs'
+    btn_block = option[:block] || 'btn-block'
     link_to (on ? "Yes" : "No"), toggle_url,
-      {class: "btn btn-block #{btn_size} btn-#{on ? 'success' : 'default'} ajax-toggle",
+      {class: "btn #{btn_block} #{btn_size} btn-#{on ? 'success' : 'default'} ajax-toggle",
         id: id,
         data: {remote: true, method: 'get'}}
   end
diff --git a/app/models/user.rb b/app/models/user.rb
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -273,9 +273,10 @@
     end
   end
 
+  # new feature, get list of available problem in all enabled group that the user belongs to
   def available_problems_in_group
     problem = []
-    self.groups.each do |group|
+    self.groups.where(enabled: true).each do |group|
       group.problems.where(available: true).each { |p| problem << p }
     end
     problem.uniq!
@@ -296,6 +297,8 @@
     end
   end
 
+  #check if the user has the right to view that problem
+  #this also consider group based problem policy
   def can_view_problem?(problem)
     return true if admin?
     return available_problems.include? problem
diff --git a/app/views/application/_submission.html.haml b/app/views/application/_submission.html.haml
--- a/app/views/application/_submission.html.haml
+++ b/app/views/application/_submission.html.haml
@@ -10,7 +10,7 @@
   %td
     = submission.source_filename
     = " (#{submission.language.pretty_name}) "
-    = link_to('[load]',{:action => 'source', :id => submission.id})
+    = link_to '[load]', download_submission_path(submission)
   %td
     - if submission.graded_at
       = "Graded at #{format_short_time(submission.graded_at)}." 
diff --git a/app/views/groups/_form.html.haml b/app/views/groups/_form.html.haml
--- a/app/views/groups/_form.html.haml
+++ b/app/views/groups/_form.html.haml
@@ -5,12 +5,23 @@
       %ul
         - @group.errors.full_messages.each do |msg|
           %li= msg
-
-  .form-group.field
-    = f.label :name
-    = f.text_field :name, class: 'form-control'
-  .form-group.field
-    = f.label :description
-    = f.text_field :description, class: 'form-control'
-  .form-group.actions
-    = f.submit 'Save', class: 'btn btn-primary'
+  .row
+    .col-md-6
+      .form-group.field
+        = f.label :name
+        = f.text_field :name, class: 'form-control'
+  .row
+    .col-md-6
+      .form-group.field
+        = f.label :description
+        = f.text_field :description, class: 'form-control'
+  .row
+    .col-md-6
+      .checkbox
+        = f.label :enabled do
+          = f.check_box :enabled
+          Enabled
+  .row
+    .col-md-6
+      .form-group.actions
+        = f.submit 'Save', class: 'btn btn-primary'
diff --git a/app/views/groups/index.html.haml b/app/views/groups/index.html.haml
--- a/app/views/groups/index.html.haml
+++ b/app/views/groups/index.html.haml
@@ -7,14 +7,16 @@
     %tr
       %th Name
       %th Description
+      %th Enabled?
       %th
       %th
 
   %tbody
     - @groups.each do |group|
-      %tr
+      %tr{:class => "#{(group.enabled?) ? "success" : "danger"}", id: "group-#{group.id}"}
         %td= group.name
         %td= group.description
+        %td= toggle_button(group.enabled?, toggle_group_path(group), "group-enabled-#{group.id}", size: ' ', block: ' ')
         %td= link_to 'View', group, class: 'btn btn-default'
         %td= link_to 'Destroy', group, :method => :delete, :data => { :confirm => 'Are you sure?' }, class: 'btn btn-danger'
 
diff --git a/app/views/groups/toggle.js.haml b/app/views/groups/toggle.js.haml
new file mode 100644
--- /dev/null
+++ b/app/views/groups/toggle.js.haml
@@ -0,0 +1,8 @@
+= render partial: 'toggle_button',
+                  locals: {button_id: "#group-enabled-#{@group.id}",button_on: @group.enabled }
+:plain
+  r = $("#group-#{@group.id}");
+  r.removeClass('success');
+  r.removeClass('danger');
+  r.addClass("#{@group.enabled? ? 'success' : 'danger'}");
+
diff --git a/config/routes.rb b/config/routes.rb
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -54,6 +54,7 @@
       post 'add_problem', to: 'groups#add_problem', as: 'add_problem'
       delete 'remove_problem/:problem_id', to: 'groups#remove_problem', as: 'remove_problem'
       delete 'remove_all_problem', to: 'groups#remove_all_problem', as: 'remove_all_problem'
+      get 'toggle'
     end
     collection do
 
@@ -92,7 +93,6 @@
       get 'download'
       get 'compiler_msg'
       get 'rejudge'
-      get 'source'
     end
     collection do
       get 'prob/:problem_id', to: 'submissions#index', as: 'problem'
diff --git a/db/migrate/20200813083020_add_enabled_to_group.rb b/db/migrate/20200813083020_add_enabled_to_group.rb
new file mode 100644
--- /dev/null
+++ b/db/migrate/20200813083020_add_enabled_to_group.rb
@@ -0,0 +1,5 @@
+class AddEnabledToGroup < ActiveRecord::Migration[5.2]
+  def change
+    add_column :groups, :enabled, :boolean, default: true
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2018_06_12_102327) do
+ActiveRecord::Schema.define(version: 2020_08_13_083020) do
 
   create_table "announcements", id: :integer, options: "ENGINE=InnoDB DEFAULT CHARSET=latin1", force: :cascade do |t|
     t.string "author"
@@ -80,6 +80,7 @@
   create_table "groups", id: :integer, options: "ENGINE=InnoDB DEFAULT CHARSET=latin1", force: :cascade do |t|
     t.string "name"
     t.string "description"
+    t.boolean "enabled", default: true
   end
 
   create_table "groups_problems", id: false, options: "ENGINE=InnoDB DEFAULT CHARSET=latin1", force: :cascade do |t|