Rails alternative for Blackboard?

Dear rails riders,

After some Google searching I gave up, instead I will try and ask
here.

Does anyone know of some (open source) RoR alternative to Blackboard?
The only thing I could find was Chalksite, <http://www.chalksite.com/

, which I can't use for obvious reasons.

If not the equivalent of Blackboard, than possibly some grade-book-
like app?

Kind regards,
Robert.