Review my new learning website: Crunch Course
roundsquare: One thought I just thought about.  You say you should "self grade" your homework.  It makes sense, but this means someone needs an answer key.What if I decide to use a textbook to structure my class.  E.g. each week we go through a chapter and do the exercises.  We may not have the answers.  Is there any way to add some "social" grading?  I realize this may be tough with trick/tough questions in textbooks, but still, I think requiring an answer key will make this tough.