The paper presents a model for addressing the critical question of opportunity to learn for students with disabilities. The model was tested through a two-year study with schools and teachers in three states. Opportunity to learn analysis is critical in this educational era of push toward access and inclusion. The study results indicate that…

New analytical tools have facilitated the exploration of the trajectories of alcohol use; however, there are a limited number of studies that explore early adolescence. A sample of 5,903 youths followed from sixth through eighth grade was used to (1) examine the trajectories of alcohol use and (2) determine the degree to which common correlates…

Randomized experiments are often considered the strongest designs to study the impact of educational interventions. Perhaps the most prevalent class of designs used in large scale education experiments is the cluster randomized design in which entire schools are assigned to treatments. In cluster randomized trials (CRTs) that assign schools to…

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.…