Help EventCalendar

I am developing an application for days and times for school and I'm using the gem EventCalendar, but I have a problem in time to paint the day of the week for a particular discipline, the discipline mathematics does not happen every day only on days Mon / Wed / Fri. When creating a discipline I submit this:

class CreateDisciplines <ActiveRecord :: Migration

       def change create_table: disciplines do | t |              t.string: name              t.integer: user_id              t.boolean: monday              t.boolean: thursday              t.boolean: wednesday              t.boolean: thursday              t.boolean: friday              t.time: hour_begin              t.time: hour_end        end              t.timestamps       end end end

class CreateEvents <ActiveRecord :: Migration

         def change create_table: events do | t |                 t.integer: discipline_id                 t.date: start_at                 t.date: end_at                 t.boolean: all_day                 t.timestamps            end        end end

You can tell me how do I create a method to paint only the day of the week a particular discipline registered?

Thank you for help.