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…

In 2003, Chicago launched "Double-Dose Algebra," requiring students with pretest scores below the national median to take two periods of math--algebra and supplemental coursework. In many schools, assignment to Double Dose changed the peer composition of the algebra classroom. Using school-specific instrumental variables within a…

The relative merits of two prominent lines of inquiry into the linkage between organizational culture and effectiveness (culture type and strong culture hypotheses) were studied with 334 colleges and universities. Findings support both approaches and suggest that alternative culture types are differentially effective on different performance…