Research on classroom peer effects has focused nearly exclusively on high-income countries and on academic skills. Little is known about peer effects in low-income countries and whether effects differ under different educational environments (e.g., teacher-directed versus child-centered, conditions of concentrated advantage or disadvantage). Based…

Forty-four Head Start classrooms were randomly assigned to enriched intervention (Head Start REDI--Research-based, Developmentally Informed) or "usual practice" conditions. The intervention involved brief lessons, "hands-on" extension activities, and specific teaching strategies linked empirically with the promotion of: (a)…