Is Pre-Kindergarten an Educational Panacea? A Systematic Review and Meta-Analysis of Scaled-Up Pre-Kindergarten in the United States

We synthesize the existing research and compute meta-analytic averages for the effects of scaled-up, publicly funded pre-kindergarten (pre-K) programs on student pre-kindergarten achievement in math and reading. Other systematic reviews of pre-K programs have focused on the effects for specific groups of students from various types of pre-K programs. We add to the literature by focusing on scaled-up pre-K often provided at the state level, which is of growing policy interest. Scaled-up programs are large state or district run programs that are available to a large portion of children before they enter kindergarten. We limit our analysis to state and districtwide pre-K programs in the United States from 2000 through 2016. In order to obtain the most accurate effect estimates, we restrict our analysis to experimental and quasi-experimental research designs with the highest internal validity. We synthesize the short-term cognitive effects of pre-K and find large positive effects of scaled-up public pre-K programs on student pre-kindergarten test scores. In particular, we find that the overall effect on math scores is over a third of a standard deviation and the overall effect on reading scores is three-fifths of a standard deviation. This review is restricted to studies focused on short term results of pre-K programs; our search uncovered only one study rigorously assessing the impacts of scaled-up pre-K programs on student achievement after kindergarten. More research is needed on the sustained effects of pre-K as policymakers debate whether to expand or adopt such programs.