BellotaStudios/Gradecraft — pull request #97 by chcholman (2012-08-18 00:52:23+00:00)
Title: Added polymorphic mappings, removed user_id from grades table

If you create an assignment, and then add a grade, you need to be able to see the user/group/team name that has earned that grade on the assignment show page. How do you write that relationship?