Prior research has established the potential for achievement gains from attending smaller classes. However, large statewide class-size reduction (CSR) policies have not been found to consistently realize such gains. A leading explanation for the disappointing performance of CSR policies is that schools are forced to hire additional teachers of…

Background/Context: One important question to educational research is whether teachers can influence student achievement over time. This question is related to the durability of teacher effects on student achievement in successive grades. The research evidence about teacher effects on student achievement has been somewhat mixed. Some education…

Results from experimental and nonexperimental studies have shown that teachers differ in their effectiveness. In addition, evidence from nonexperimental studies has indicated that teacher effects last for 3 years in elementary grades. This study uses data from Project STAR and its follow-up study, the Lasting Benefits Study, to examine whether…

This article addresses three questions: Does reduced class size cause higher academic achievement in reading, mathematics, listening, and word recognition skills? If it does, how large are these effects? Does the magnitude of such effects vary significantly across schools? The authors analyze data from Tennessee's Student/Teacher Achievement Ratio…

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…