Read Haley's post and my response at the link above:

robin said...
I think the connection between grades and doing what it takes to get an "A" is at the heart of behaviorism. However, if there is any negative reinforcement (e.g., the professor tells the student that cheating is not acceptible and will be punished) then it keeps the behavior within an acceptible parameter (or at least, that is what makes sense to me).