This article examines the power analyses for the first wave of group-randomized trials funded by the Institute of Education Sciences. Specifically, it assesses the precision and technical accuracy of the studies. The authors identified the appropriate experimental design and estimated the minimum detectable standardized effect size (MDES) for each…

Interest has rapidly increased in studies that randomly assign classrooms or schools to interventions. When well implemented, such studies eliminate selection bias, providing strong evidence about the impact of the interventions. However, unless expected impacts are large, the number of units to be randomized needs to be quite large to achieve…

Grade retention has been controversial for many years, and current calls to end social promotion have lent new urgency to this issue. On the one hand, a policy of retaining in grade those students making slow progress might facilitate instruction by making classrooms more homogeneous academically. On the other hand, grade retention might harm…

Many researchers who study the relations between school resources and student achievement have worked from a causal model, which typically is implicit. In this model, some resource or set of resources is the causal variable and student achievement is the outcome. In a few recent, more nuanced versions, resource effects depend on intervening…

Considers social and ethnic inequity in access to resources for mathematics learning in eighth grade using data from 41 states and territories participating in the 1992 Trial State Assessment of the National Assessment of Educational Progress. Findings indicate that state differences in access to key educational resources are important. (SLD)

Two policy options for improving teacher competence, inservice training and regular classroom supervision, were studied through a survey of approximately 400 rural primary schools in Thailand. Results do not indicate improvement resulting from inservice training but do show improvement resulting from intensity of supervision. Implications for…