This report examines one component of the current school accountability system--learning gains. We find that learning gain percentages are affected by a variety of factors including starting achievement level, socioeconomic status, and English language learner status when the current definition of learning gains is used. Hence, we propose a new…

Instructional time is a fundamental educational input, yet we have little causal evidence about the effect of longer school days on student achievement. This paper uses a sharp regression discontinuity design to estimate the effects of lengthening the school day for low-performing schools in Florida by exploiting an administrative cutoff for…

Background: Cluster-randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…