First of all, its bright students teaching other bright students--if that wasn't clear. Second, you are only looking at half the equation. That 7th grader spe

First of all, its bright students teaching other bright students--if that wasn't clear. Second, you are only looking at half the equation. That 7th grader spending time with a smart 6th grader is also spending time with a smart 8th grader. The benefit comes from the (fact? hypothesis?) that bright children within a couple of years from each other will get a hell of a lot more bang for their buck than the time they spend with their (statistically) relatively average teachers that have lost touch with that part of their development cycle.