This paper presents evidence on the amount of classroom variation in gains across various domains of achievement within the Tennessee Voluntary Pre-Kindergarten (TN-VPK) program; the data are taken from the randomized control trial (RCT) design of the TN-VPK evaluation. This study explores areas where those differences are largest, and offers…

Head Start programs currently provide early childhood education and family support services to more than 900,000 low-income children and their families across the United States with an annual budget of around $8 billion in state and federal funds. Researchers and policy makers have debated the program's effectiveness since its inception in 1964.…

This paper capitalizes on the addition of geocodes for Head Start centers in which children were randomly assigned to address questions about the role of neighborhood characteristics in moderating impacts of assignment to the Head Start program. Researchers explore the extent to which impacts of assignment to Head Start on outcomes for children…

The authors are presently in the fourth year of a six-year, lottery-based randomized control trial (RCT) studying the effectiveness of nine Colorado charter schools that have implemented Core Knowledge®. Core Knowledge (CK) is a comprehensive K-8 curriculum for language arts, math, science, social studies, visual arts, and music that is intended…

With the increased population of English learners (ELs), educators need programs that help students access academic content while learning to understand, speak, read, and write English (Tharp, Estrada, Dalteen, & Yamaguchi 2000; Echevarria, Short & Powers, 2006). ELs come into U.S. schools needing to learn the same grade-level content as…

In experimental studies, researchers are often interested in secondary research questions that explore important aspects of main findings, such as whether or not program effects vary according to the level of fidelity in which the program has been implemented; or according to the dosage received by individuals participated in the program. In this…

This study seeks to answer the following question: Are impacts on Head Start classroom quality associated with impacts of Head Start on children's learning and development? This study employs a variety of descriptive and quasi-experimental methods to explore the role of classroom quality as a mediator or mechanism of Head Start impacts. This…

Head Start is the largest publicly funded preschool program in the U.S., and one of its primary goals is to improve the school readiness of low-income children. As has been widely reported, the first randomized trial of Head Start in the program's history found some evidence that it is achieving this goal. Receiving one year of Head Start had…