I previously have worked with Blackboard as both a student and an instructor. Aside from the fact that Blackboard, eLearning, WebCT, etc are all crappy tools, I believe their API for access is completely closed off so developing an Android app relies mostly on Blackboard's end to develop it.
I know it's not the answer you're looking for, but there are other tools on the web like Blackboard that provide your own private course set up to keep track of your documents for class, etc. If you just keep on top of what's being uploaded for Bloackboard then you can keep a pretty nice management suite for all of your coursework, but it obviously won't be up to date with what your teacher uploads.
I hope you find something that works, cause I've looked into this myself. Let me know if you have any luck.