[Lewisham]

I certainly do need to interact with Khan Academy more often, I need to brush up on my probabilities for technical interviews this summer, so I'll use that as a step into the product.

FWIW, having seen Salman Khan speak, it's hard not to be swept up with his cause. He's a man on a mission, and if anyone has the vision and charisma to pull off Khan Academy's goals, it's him.

[aik]

I think an important distinction is also that the purpose of the math test graph is to specifically quantify prior learning (ie. it provides a reasonably realistic measurement of learning) -- this is not gamification necessarily. The badges are gamification. Our goal should be realistic and effective quantification of learning/improvement (passive feedback that generally increases intrinsic motivation), rather than implementing external motivators or artificial targets (which badges typically are).