add and remove try but missing concepts

<table><tr>
        <% form_tag (:action => :add_remove_camper) do %>
           <td>
           <%= collection_select(:milk, :moos,
               @team_campers, :id, :full_name,
              {}, {:html => { :size => 20 }} )%><br />

Half the point of the form helpers that use instance variables is that the first one (:milk) is the name of the instance varaible and the second (:moos) is the name of the attribute you are editing. You're not editing an existing object (or creating one), so you could just be using select_tag and collection_for_select/options_for_select

<%= collection_select(:milk, :moos,
               @team_campers, :id, :full_name,
              {}, {:class => 'foo'} )

Should set the class of that item to foo. The text_are helpers take

Fred