On mobile and wouldn't be sure where to find it anyway, but this has been done! It turned out that the proximity of the reward was critical. A cash prize for a

On mobile and wouldn't be sure where to find it anyway, but this has been done! It turned out that the proximity of the reward was critical. A cash prize for a end of unit grade had nearly no effect, while an immediate cash prize tied to, say, a daily quiz showed some decent effect on the particular quiz/assignment. The take away from the study was that shorter feedback loops are important. Questions were also raised on intrinsic vs extrinsic motivators.