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…

The What Works Clearinghouse (WWC) identifies existing research on educational interventions, assesses the quality of the research, and summarizes and disseminates the evidence from studies that meet WWC standards. The WWC aims to provide enough information so educators can use the research to make informed decisions in their settings. This…

Theories regarding the long-term effects of educational interventions are often assumed, but rarely tested using experimental methods. In the following commentary, we argue that the shortage of randomized control trials with long-term follow-up presents serious problems for the field, as it hampers our ability to develop educational programs that…

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…

Theories regarding the long-term effects of educational interventions are often assumed, but rarely tested using experimental methods. In the following commentary, we argue that the shortage of randomized control trials with long-term follow-up presents serious problems for the field, as it hampers our ability to develop educational programs that…

Randomized trials are often conducted with separate randomizations across multiple sites such as schools, voting districts, or hospitals. These sites can differ in important ways, including the site's implementation, local conditions, and the composition of individuals. An important question in practice is whether--and under what…

As the number of publicly funded early childhood education (ECE) programs increases, policymakers will need empirical evidence to justify the taxpayer investment. Such justification will require a stronger understanding of the essential components of an ECE program's design, as well as solid evidence on which components, or constellations of…

In a randomized controlled trial of a teacher data-use intervention, the Linking Study tested the impacts of a cyclical and collaborative process that linked teachers' data on instructional practice with data on their students' learning. This article describes the theory of the intervention and its roots in the literature as a backdrop for an…

Estimating treatment effects for subgroups defined by posttreatment behavior (i.e., estimating causal effects in a principal stratification framework) can be technically challenging and heavily reliant on strong assumptions. We investigate an alternative path: using bounds to identify ranges of possible effects that are consistent with the data.…

Structural quality in childcare centers is considered a precondition for process quality, which in turn is related to children's outcomes. However, the evidence on relations between structural and process quality is mixed. Moreover, despite strong theoretical claims, empirical evidence supporting the indirect relation of structural features…

The United States considers educating all students to a threshold of adequate outcomes to be a central goal of educational justice. The No Child Left Behind Act introduced evidence-based policy and accountability protocols to ensure that all students receive an education that enables them to meet adequacy standards. Unfortunately, evidence-based…

A growing body of research exists on the effectiveness of classroom-based intervention programs to prevent and ameliorate social, emotional, and learning difficulties demonstrated by young children at risk for emotional and behavioral disorders (EBD). Yet, little research has examined the influence of these targeted intervention programs on the…

Purpose/Objective: Under the reauthorized Every Student Succeeds Act (ESSA), states and districts retain greater discretion over the measures included in school quality report cards. Moreover, ESSA now requires states to expand their measurement efforts to address factors like school climate. This shift toward more comprehensive measures of school…

We assessed the impacts of a teacher professional development program for public and private kindergartens in the Greater Accra Region of Ghana. We examined impacts on teacher professional well-being, classroom quality, and children's readiness during one school year. This cluster-randomized trial included 240 schools (teachers N = 444; children N…

Introduction: Secondary schools have the potential to promote health-related fitness (HRF) and physical activity within and outside school hours. As such, schools are often chosen as the setting to implement child and adolescent physical activity programs. School-based programs often utilise teachers as delivery agents, but few studies examine…