Ya did it but, and there is always a but:
1. When I try to added a lesson to a class that is already in the database, I get 'Index or primary key cannot contain a Null value' error.
2. When I add a new record after selecting the appropriate division, the subform populates with every lesson rather than letting me choice which specific lessons apply to that class.
Man, I am starting to feel like a real pain in the ars.