This study is a randomized controlled trial that assessed the impact of Early College High Schools on students' high school graduation, college enrollment, and college degree attainment, as well as students' high school experiences using extant data and survey data. The study included 10 Early Colleges that enrolled students in Grades 9 to 12 in…

This article presents findings from a lottery-based study of the impacts of a broad set of 33 charter middle schools across 13 states on student achievement. To estimate charter school impacts, we compare test score outcomes of students admitted to these schools through the randomized admissions lotteries with outcomes of applicants who were not…

This article presents the findings of an evaluation of the eMINTS (enhancing Missouri's Instructional Networked Teaching Strategies) professional development program. eMINTS is an intensive teacher professional development program designed to promote inquiry-based learning, support high-quality lesson design, build community among students and…

Stereotype threat is frequently purported to be an important determinant of gender gaps in math. Unlike prior studies, which mostly occur in lab settings, I use data from the National Assessment of Educational Progress (NAEP)--a large, representative assessment of U.S. children--where through a design quirk, students are randomly assigned test…

Interest has rapidly increased in studies that randomly assign classrooms or schools to interventions. When well implemented, such studies eliminate selection bias, providing strong evidence about the impact of the interventions. However, unless expected impacts are large, the number of units to be randomized needs to be quite large to achieve…

This article examines how controlling statistically for baseline covariates, especially pretests, improves the precision of studies that randomize schools to measure the impacts of educational interventions on student achievement. Empirical findings from five urban school districts indicate that (1) pretests can reduce the number of randomized…