Research shows that early childhood education (ECE) can strongly influence children’s learning and development. Universal prekindergarten (UPK) offers free access to all age-eligible children, yet by 2019–2020 only 10 states and the District of Columbia had adopted it. Despite growing interest, evidence on its long-term academic impact remains limited. A recent study examined Wisconsin’s partial-day UPK program, known as 4K, and its effects on third-grade reading and math scores, focusing on differences by economic status and race/ethnicity. Using administrative data from 292 school districts, the study analyzed trends in standardized test scores (Wisconsin Knowledge and Concepts Examination – WKCE) from 2001 to 2014, applying a difference-in-differences model to estimate the program’s effects.
Results from the intent-to-treat (ITT) analysis, based on whether districts offered 4K, showed a modest but positive effect on reading scores overall (up to +0.10 SD). Gains were particularly strong for Hispanic students (+0.33 SD), potentially reducing the White-Hispanic reading gap by nearly 40%. When looking at treatment-on-the-treated (TOT) effects, based on actual participation, the estimated impact was larger. Full district participation in 4K was associated with a +0.13 SD increase in reading overall, and a +0.49 SD gain for Hispanic students. Effects for Black students were also positive, though not statistically significant after adjusting for other factors. In math, overall effects were small and not significant (+0.03 SD). However, Black students saw the largest benefits: a +0.25 SD gain in the ITT analysis and +0.39 SD in the TOT analysis – an improvement equivalent to a 38% increase in math proficiency and a narrowing of the Black-White math gap by about 40%. Math outcomes for other groups were not statistically significant.
In sum, Wisconsin’s part-day UPK program had modest overall effects but showed stronger and more sustained benefits for Hispanic and Black students. The limited duration, access, and quality of the program may have reduced its full potential. Expanding to full-day schedules, improving standards, and reducing barriers to participation—especially for students of color—could help strengthen equity and maximize long-term academic benefits.
Source: Yang, H. (2024). The Effects of Wisconsin’s Universal Prekindergarten Program on Third-Grade Academic Achievement. American Educational Research Journal, 61(6), 1237-1271.