anchor.diff:      <div class="control-group">
         <%= f.label :title, :class => 'control-label' %>
         <div class="controls">
  -        <%= f.text_field :title, :class => 'text_field span7', :placeholder => "What's this session about?" %>
  +        <%= f.text_field :title, :class => 'text_field span7', :placeholder => "What's this session about?", :required => 'required' %>
         </div>
       </div>
   
  
positive.code:       <%= f.label :start_at, :class => 'control-label' %>
        <div class="controls">
          <div class="datetimepicker input-append datetime">
            <%= f.text_field :start_at, :value => datetime_format(@lesson_plan_entry.start_at) %>
            <span class="add-on">
              <i data-time-icon="icon-time" data-date-icon="icon-calendar"></i>
            </span>
  
negative.code:       <%= f.label :end_at, :class => 'control-label' %>
        <div class="controls">
          <div class="datetimepicker input-append datetime">
            <%= f.text_field :end_at, :value => datetime_format(@lesson_plan_entry.end_at), :required => 'required' %>
            <span class="add-on">
              <i data-time-icon="icon-time" data-date-icon="icon-calendar"></i>
            </span>
  