Public Pre-K Effects on Public School Enrollment: Evidence from Washington, D.C.

• In Event: Early childhood care and education enrollment: Policy drivers and impacts

Abstract

Enrollment in pre-kindergarten programs has reached an all-time high (Friedman-Krauss et al., 2024), with publicly funded pre-k accounting for 60 percent of total enrollment (Little, 2021). A rich literature shows positive child and family benefits from public pre-K participation (Gray-Lobe, Pathak, & Walters, 2022; Duncan & Magnuson, 2013).

One under-examined dimension of public pre-k is how it might affect later public school enrollment patterns. Stability in enrollment is economically important for U.S. public schools, and school continuity provides benefits for children and families (Reynolds et al., 2009; Schwartz et al., 2017).  Ecological frameworks emphasize the importance of strong ties between home, school, and community in supporting stability across educational transitions (Rimm-Kaufman & Pianta, 2000). Public pre-K may strengthen these connections, easing the transition into formal schooling and fostering greater continuity and “stickiness” in the public school system (Dee, 2023; Lieberman, 2024).

While many have hypothesized that public pre-K might influence later public school enrollment, its system-wide impact remains speculative. This is especially important as nearly 60% of public elementary schools now offer pre-K (Shapiro et al., 2025), positioning it as a natural bridge into the broader education system.

I study the impact of public pre-K expansion on K-5 public education enrollment trends in Washington, D.C.  The 2008 Pre-K Act created a high-quality, universal pre-k program for all 3- and 4-year-olds. Today, D.C. has the nation’s most comprehensive pre-k system, with 88% of 4-year-olds enrolled (NIEER, 2024). Building on prior lottery-based studies (e.g., Braga et al., 2024), I estimate system-level effects using 25 years of population-wide data, addressing calls for more generalizable evidence on pre-K impacts (Weiland et al., 2024; Phillips et al., 2017).

Research Questions:

Specifically, I address three questions:

1. 
   

   What is the effect of D.C.'s public pre-K expansion on K-5 public school enrollment patterns?

   
   


2. 
   

   Does the pre-k expansion shift students between traditional and public charter sectors and/or increase the share of school-age eligible population in the public system?   

   
   


3. 
   

   Do changes in enrollment patterns differ by race/ethnicity and economic status, and do they shift the demographic composition of D.C.’s public school system?

   
   

Using population-level administrative data, I use comparative interrupted time series (CITS) to examine enrollment patterns across different grades and cohorts of students relative to their pre-K policy exposure. By comparing pre- and post-policy changes across multiple cohorts relative to their pre-k exposure over a 25-year period, the CITS framework helps isolate the policy's impact from other underlying enrollment trends or shocks.

Preliminary Findings

Public pre-k expansion had a large, significant, positive effect on K-5 public school enrollment in Washington, D.C. The system-wide enrollment growth is driven by shifts in DC Public Schools (DCPS), a sector that went from a period of enrollment decline to a period of growth in the post-policy period. The share of eligible children enrolled in public kindergarten also increased after implementation, suggesting that more families opted into the public system because of the pre-K expansion.

Author

• Sofia Wilson, Stanford University
  Presenting Author