app/views/course_notifications/_form.html.erb
<%= form_for @notifier, url: organization_course_course_notifications_path do |f| %>
<div class="form-group">
<%= f.label :topic %>
<%= f.text_field :topic, class: 'form-control' %>
</div>
<div class="form-group">
<%= f.label :message %>
<%= f.text_area :message, class: 'form-control', rows: 10 %>
</div>
<%= f.submit 'Send email to every course participant', class: "btn btn-danger", data: { confirm: "Do you really want to send this message to every participant?" } %>
<% end %>