Multisite trials, in which individuals are randomly assigned to alternative treatment arms within sites, offer an excellent opportunity to estimate the cross-site average effect of treatment assignment (intent to treat or ITT) "and" the amount by which this impact varies across sites. Although both of these statistics are substantively…

Purpose: The past decade has seen considerable debate about how to best evaluate the efficacy of educational improvement initiatives, and members of the educational leadership research community have entered the debate with great energy. Throughout this debate, the use of randomized experiments has been a particularly contentious subject. This…

The ESEA Blueprint for Reform states that teachers need "effective, ongoing, job-embedded, professional development that is targeted to student and school needs… [and] aligned with evidence of improvements in student learning." Unfortunately, the professional development approaches advocated, though sensible and compelling in theory,…