On the optimal allocation of students when peer effect works: Tracking vs Mixing.

The belief that the behaviour and outcomes of compulsory school students are affected by their peers has been important in shaping education policy. I analyze two polar education systems -tracking and mixing- and propose several criteria for their comparison. The system that maximizes average human capital, I find, depends crucially on the level of complementarity between peer effects and individuals' ability. I also find that when mean innate ability is much higher among the rich than among the poor, the system that best maximizes average human capital is mixing. However, there is no unanimity in the overall population so as to which system to choose.