This study is the first large RCT of a state-funded pre-k program and one of only two such studies ever conducted of a public preschool program in the United States. As such, it provides uniquely credible evidence in the area of early childhood education.
While the study found positive short-term effects on child achievement (at the end of the pre-k year), these effects dissipated as children entered elementary school and turned modestly negative by third grade. At the third-grade follow-up, the control group scored significantly higher in math and science achievement than the pre-k group.
