This seems to have worked for me. For the first part of high school I was a terrible student, then in one technical lab-based class with a lot of opportunity for student interaction, I started getting way better grades on the quizzes than everyone else, and earned the admiration of some of my peers for it. I thought "This feels kinda good," and next year (my last year of high school) I got straight As in all classes. And then I got more straight As through 4 years of undergrad.
Here's an internal dialogue I just had.
Q: How do we test rationality skills?
A: We haven't come up with a comprehensive test yet.
Q: Maybe we can test some part of rationality?
A: Sure. For example, you could test resistance to akrasia by making two contestants do some simple chores every day. The one who fails first, loses.
Q: That seems like a pointless competition. If I'm feeling competitive, why would I ever skip the chores and lose?
A: Whoa, wait. If competitiveness can cure akrasia, that's pretty cool!
Now we just need to figure out how to make people more competitive in the areas they care about...