As hours per day are inherently a limited resource, increasing daily instruction time reduces the amount of time pupils can dedicate to other activities outside school. We study how the effect of longer school days on achievement varies across students and schools. We exploit a large-scale reform of school schedules that substantially increased…

There is a persistent debate over the role of scale of operations in education. Some argue that school franchises offer educational services more effectively than do small independent schools. Skeptics counter that large, centralized operations create hard-to-manage bureaucracies and foster diseconomies of scale and that small schools are more…