We examine whether the sorting of differently achieving students into differently sized classes results in a regressive or compensatory pattern of class sizes for a sample of national school systems. Sorting effects are identified by subtracting the causal effect of class size on performance...

Teachers differ greatly in how much they teach their students, but little is known about which teacher attributes account for this. We estimate the causal effect of teacher subject knowledge on student achievement using within-teacher within-student variation, exploiting a unique Peruvian...

We study a mentoring program that aims to improve the labor-market prospects of schoolattending adolescents from disadvantaged families by offering them a university-student mentor. Our RCT investigates program effectiveness on three outcome dimensions that are highly predictive of adolescents'...

Teachers differ greatly in how much they teach their students, but little is known about which teacher attributes account for this. We estimate the causal effect of teacher subject knowledge on student achievement using within-teacher within-student variation, exploiting a unique Peruvian...