Given that previous findings on the social distribution of the effects of small classes have been mixed and inconclusive, in the present study I attempted to shed light on the mechanism through which small classes affect the achievement of low- and high-achieving students. I used data from a 4-year, large-scale, randomized experiment (project…

Recent research from randomized experiments on class size points to positive effects of small classes that persist for several years, but the evidence about the social distribution of effects is less clear. Some scholars have contended that the immediate effects of small classes are larger for minorities and for disadvantaged persons (e.g., J. D.…