High-quality preschool programs are heralded as an effective policy tool to promote the development and life-long wellbeing of children from low-income families. Yet evaluations of recent preschool programs produce puzzling findings, including negative impacts, and divergent, weaker results than were shown in demonstration programs implemented in…

Identifying effective methods that can counteract seasonal trends in learning loss is essential to ensure continuous literacy growth of young learners. Computer-assisted instruction (CAI) is a solution for providing an effective summer literacy program that could help offset summer learning loss. In this study, four-year-old students from South…

Background: The language of the science curriculum is complex, even in the early grades. To communicate their scientific observations, children must produce complex syntax, particularly complement clauses (e.g., "I think it will float;" "We noticed that it vibrates"). Complex syntax is often challenging for children with…

This paper reviews research on the design and effectiveness of preschools in the United States. Three randomized controlled trials that enrolled roughly 350 total children in demonstration studies during the 1960s and 1970s shape much of the current discussion of preschool. We examine what these studies and more recent ones based on random…

Background/Context: Early childhood education research has consistently found evidence of immediate, positive effects on developmental outcomes. Despite these strong initial benefits, follow-up analyses often reveal that these effects fadeout in the years following participation (e.g., Bailey et al., 2017, Clements et al., 2013; Lipsey et al.…

Social-emotional learning (SEL) programs are frequently evaluated using randomized controlled trial (RCT) methodology as a means to assess program impacts. What is often missing in RCT studies is a robust parallel investigation of the multi-level implementation of the program. The field of implementation science bridges the gap between the RCT…