Association for Public Policy Analysis & Management

Full-day kindergarten as a policy lever has been an area of considerable action over the past two decades. While data from the 1998 and 2010 cohorts of the Early Childhood Longitudinal Study documents that full-day kindergarten participation has increased from 56 to 80 percent of kindergarten students, other aspects of the early childhood experience have remained relatively stable in the same timeframe, including preschool and Head Start participation and small class size in kindergarten.

This paper explores the impact of full-day kindergarten availability on inequality by coupling data from the Stanford Education Data Archive with data on full-day kindergarten expansions across states and over the 1990s and 2000s. By leveraging variation across states and—within one state, across districts—and over time, the research design seeks to isolate the effects of full-day kindergarten expansions on subsequent student achievement and racial/ethnic achievement gaps. This work speaks directly to the impact of state education policies around full-day kindergarten, rapidly changing in the time period of interest, on educational inequality.

Nearly all students who attend school outside the home participate in kindergarten in the United States and 75 percent of students in kindergarten are now in full-day settings. The policy activity on full-day kindergarten has all taken place at the local and state levels, with 10 states and DC providing full-day kindergarten at no charge to all children per state statute (Children’s Defense Fund, 2014). According to the Current Population Survey (CPS) October Enrollment Supplement, 37 states were at 40 percent or below in full-day kindergarten enrollment in the 1990s. By 2010, only two states had approximately 40 percent or less of their kindergarten students in full-day settings.

Despite its popularity, there is a very small literature on the impact of full-day kindergarten, largely lacking in rigor and increasingly dated for application to current contexts. In observational studies using the 1998 ECLS-K, researchers found significant differences between full- and half-day kindergarteners on literacy and mathematics assessments at the end of the kindergarten year (Cannon et al. 2006, DeCicca 2007, Lee et al. 2006, Votruba-Drzal et al. 2008). These full-day kindergarten advantages are somewhat persistent into first grade, but not longer present in third grade or fifth grade follow-ups. Experimental results suggest that full-day kindergarten has a sizable, positive effect (0.31 s.d.) on end-of-kindergarten literacy skills (Gibbs 2014). In particular, Hispanic students benefitted greatly from assignment to full-day kindergarten as compared to their peers in half-day, nearly closing the Hispanic-non-Hispanic literacy skills gap by the end of the kindergarten year.

This study further investigates the potential for full-day kindergarten to remediate school-entry race/ethnicity achievement gaps, answering a different, policy-relevant question about the systemic effects of a policy change. In addition, the study uses newly available data sources to explore these questions in more current policy contexts with a focus on achievement gaps. No work to date has leveraged the dramatic changes in full-day kindergarten provision in the 2000s to look specifically at implications for inequality.