Effects of Public Pre-K for 3-Year-Olds on Secondary School Outcomes: Early Evidence from DC Centralized Lottery

• In Event: The Long-Term Effects of Preschool Interventions

Abstract

Public investment in early childhood education has expanded substantially in recent decades, yet evidence on the long-term effects of programs serving children as young as age three remains limited. This study examines the causal impact of enrollment in a large-scale, universal public pre-kindergarten program for 3-year-olds (Pre-K3) in the District of Columbia on secondary school outcomes. Leveraging the centralized school assignment lottery as a quasi-experimental design, we follow applicants for up to twelve years to estimate the effects of Pre-K3 participation on a range of middle and high school outcomes, including credit accumulation, completion of advanced coursework, suspensions, and grade retention.

The policy focus of this study is the public Pre-K program in Washington, DC, with a specific emphasis on public Pre-K for 3-year-olds delivered in public schools. Although DC Pre-K serves 3- and 4-year-olds (in Pre-K3 and Pre-K4), we will focus our study on school-based Pre-K3. We do so for two reasons. First, DC is unique in the nation in its large-scale service provision for 3-year-olds; focusing on this one-year intervention allows us to fill a critical gap in the existing literature and generate actionable insights for policymakers, practitioners, and researchers. Second, school-based enrollment is organized around a common lottery, My School DC, providing a sound methodological basis for evaluation.

This project builds on prior research documenting positive impacts of DC’s Pre-K3 program on early elementary outcomes and extends the analysis to adolescence, a critical period for shaping long-term educational attainment and labor market trajectories. By linking lottery data to administrative education records, we estimate intent-to-treat and treatment-on-the-treated effects, providing rigorous evidence on the persistence of early childhood interventions. We further examine heterogeneity in impacts by key sociodemographic characteristics, including neighborhood poverty exposure, as well as variation by program quality, offering insight into which populations and program features drive effectiveness.

Despite strong evidence that early childhood investments can improve school readiness, little is known about whether these benefits persist into adolescence, particularly for programs targeting 3-year-olds. This gap is notable given growing policy interest in expanding access to earlier preschool and interdisciplinary evidence suggesting that earlier interventions may yield larger returns. By providing new causal evidence on long-term outcomes and economic impacts, this study contributes to the policy debate on the value of early childhood education investments. The findings will inform policymakers, program administrators, and advocates considering the expansion of Pre-K3 programs, particularly in urban settings serving diverse and economically disadvantaged populations.

Author

• Breno Braga, Urban Institute
  Presenting Author