Programs that improve teaching effectiveness represent a core strategy to improve student educational outcomes and close student achievement gaps. This article compiles empirical values of intraclass correlations for designing effective and efficient experimental studies evaluating the effects of these programs. The Early Childhood Longitudinal…

Using multilevel models, the authors tested the hypothesis that high schools, through their curricular policies, operate as mechanisms that help members of privileged groups to take better advantage of postsecondary opportunities. The analysis was based on a 7-year follow-up study of 44,666 Israeli students who graduated from 385 high schools in…