This article presents evidence from a large-scale randomized controlled trial of the effects of four supplemental reading comprehension curricula (Project CRISS, ReadAbout, Read for Real, and Reading for Knowledge) on students' understanding of informational text. Across 2 school years, the study included 10 school districts, more than 200…

This report presents estimates from a large-scale, multi-district RCT (randomized controlled trial) on the effectiveness of a summer reading program on improving student reading comprehension for economically disadvantaged grade 3 students reading below the 50th percentile nationally. This study focused on the summer between grades 3 and 4 for…

Collaborative Strategic Reading (CSR) is a set of instructional strategies designed to improve the reading comprehension of students with diverse abilities (Klingner and Vaughn 1996). Teachers implement CSR at the classroom level using scaffolded instruction to guide students in the independent use of four comprehension strategies; students apply…

Randomized field trials were used to examine the impact of the Teacher Study Group, a professional development model, on first grade teachers' reading comprehension and vocabulary instruction, their knowledge of these areas, and on the corollary comprehension and vocabulary achievement of their students. The multi-site study was conducted during…

This report lays out the design for the Evaluation of Reading Comprehension Interventions, which is assessing supplemental reading comprehension programs for fifth-grade students in Title I schools. The key design parameters are described. The report itself provides the rationale for these decisions and discusses design and measurement issues,…