The motivation for this paper is the authors' recent work on several randomized control trials in which they found the primary result, which averaged across subgroups or sites, to be moderated by demographic or site characteristics. They are led to examine a distinction that the Institute of Education Sciences (IES) makes between "confirmatory"…

The concept of "implementation fidelity" is broadly used to capture the extent to which an intervention is executed as intended by the designers of the intervention (Century, Rudnick, & Freeman, 2010; Huntley, 2005, McNaught, Tarr, & Sears, 2010, Munter, 2010). Though implementation fidelity instruments are often used to assess…

During the past decade, the use of standardized benchmark measures to differentiate and individualize instruction for students received renewed attention from educators. Although teachers may use their own assessments (tests, quizzes, homework, problem sets) for monitoring learning, it is challenging for them to equate performance on classroom…

This paper provides practical guidance for researchers who are designing and analyzing studies that randomize schools--which comprise three levels of clustering (students in classrooms in schools)--to measure intervention effects on student academic outcomes when information on the middle level (classrooms) is missing. This situation arises…

This guide summarizes "Effective Programs for Struggling Readers: A Best Evidence Synthesis," a research review conducted by Johns Hopkins University's Center for Research and Reform in Education. The purpose of the review was to evaluate the achievement outcomes of alternative approaches for struggling readers in grade K-5: (1) one-to-one…

I estimate the impact of attending a magnet school on student achievement in mathematics in a moderately large Southern district. Admission to magnet schools is through lotteries. Actual attendance by lottery winners is of course voluntary. I use lottery outcomes as instruments to control for bias due to self-selection of enrollees. Because…