There is a need for robust evidence about which educational interventions work in preschool to foster children's cognitive and socio-emotional learning (SEL) outcomes. Lab-based individually randomized experiments can develop and refine such interventions, and field-based randomized experiments (e.g., cluster randomized trials) evaluate their…

This article assesses the likely generalizability of educational treatment-effect estimates from regression discontinuity designs (RDDs) when treatment assignment is based on academic pretest scores. Our assessment uses data on outcome and pretest measures from six educational experiments, ranging from preschool through high school, to estimate…

This article assesses the likely generalizability of educational treatment-effect estimates from regression discontinuity designs (RDDs) when treatment assignment is based on academic pretest scores. Our assessment uses data on outcome and pretest measures from six educational experiments, ranging from preschool through high school, to estimate…

Pretense is a naturally occurring, apparently universal activity for typically developing children. Yet its function and effects remain unclear. One theorized possibility is that pretense activities, such as dramatic pretend play games, are a possible causal path to improve children's emotional development. Social and emotional skills,…

Although extensive research exists on vocabulary instruction during book reading in preschool classroom, comparatively little research has been conducted on vocabulary exposure in classroom play contexts and child vocabulary outcomes. The purpose of this study was to examine Head Start teacher and child vocabulary use in dyadic play sessions and…

The primary purpose of the 2017-2018 NC Pre-Kindergarten (NC Pre-K) Evaluation was to examine the effectiveness of the NC Pre-K Program using a randomized controlled trial (RCT) design. The major issue addressed by this type of study is around the benefits of offering children access to enrollment in NC Pre-K. An RCT is considered the…

The primary purpose of the 2017-2018 NC Pre-Kindergarten (NC Pre-K) Evaluation was to examine the effectiveness of the NC Pre-K Program using a randomized controlled trial (RCT) design. Because children are randomly assigned to either receive NC Pre-K (treatment) or not (control) in an RCT, differences in outcomes can be causally attributed to…

This study evaluated the efficacy of the Preschool First Step (PFS) to Success early intervention for children at risk for attention deficit hyperactivity disorder (ADHD). PFS is a targeted intervention for children 3-5 years old with externalizing behavior problems and addresses secondary prevention goals and objectives. As part of a larger…

Research Findings: This study examined the contribution of several classroom experience measures (classroom characteristics, teacher characteristics, and teacher-child interactions) to preschoolers' improvement in visuomotor integration. Children (N = 467) ranged in age from 3 to 5 years old and were enrolled in 115 classrooms in 5 U.S. states.…

This article reports on a 4-year follow-up study from the Learning Experiences and Alternative Program for Preschoolers and Their Parents (LEAP) randomized trial of early intervention for young children with autism. Overall, participants from LEAP classes were marginally superior to comparison class children on elementary school outcomes specific…

Results from a cluster randomized trial of the impact of the Tools of the Mind pre-kindergarten curriculum on preschoolers' achievement, self-regulation, and social behavior are reported. Sixty classrooms with four-year-old children (N=877) were assigned to implement either the Tools curriculum (N=32 classrooms; 498 children) or the usual pre-k…

Research Findings: This study compared the effects of content-based shared book-reading instruction versus an explicit vocabulary-only condition on the vocabulary development of preschool dual language learners (DLLs). Using shared book reading as the mode of instruction, we randomly assigned 48 bilingual preschool teachers and 281…

This article reports on a 4-year follow-up study from the Learning Experiences and Alternative Program for Preschoolers and Their Parents (LEAP) randomized trial of early intervention for young children with autism. Overall, participants from LEAP classes were marginally superior to comparison class children on elementary school outcomes specific…

Studies of small-scale "model" early-childhood programs show that high-quality preschool can have transformative effects on human capital and economic outcomes. Evidence on the Head Start program is more mixed. Inputs and practices vary widely across Head Start centers, however, and little is known about variation in effectiveness within…