More on motivation and pay incentives . . .

Ethan posted the following comment to my last post on motivation.  He poses a question at the end of the comment.  Anyone have an answer?

In my career as a classroom teacher I can recall maybe a dozen moments that felt like true epiphanies on my journey toward becoming an effective teacher. One of those aha moments was when I realized that the students that were doing their homework and the students who weren't when they were offered points for doing so were the same students who did and didn't when there were no points involved. Why was I spending all that time processing papers to give students points when it was having no impact on whether they would do the work???!!!!



Now, here is what I really want to share. Why do teachers have to discover this on their own? What are the essential conditions that allow people to move beyond a world view that places more weight on how they feel about what must be right than what research shows is clearly the case?
 
I believe that part of the answer is in the mental models that we bring to the work.  It just makes sense that giving rewards will result in students and adults working harder to achieve the reward.  After all, isn't that what WE DID when we were students?  For most of us that became teachers, grade point average was an important motivator, more important perhaps than the learning itself.  It worked for me so my mental model is influenced by my personal experience.  To shift the mental model we must create situations that change the experience like you had with your aha moment. 
 
Another example of Ethan's question can be found in this Seattle Time's article about a Vanderbilt University study finding that teacher bonuses do not boost test scores.  This study, however, will be ignored by those reformers in high places promoting teacher salary being tie to student test scores.  The mental models are strong such that studies such as these are minimized.  On the other hand, teacher unions will use it to support their mental model that pay incentives don't work.