Abstract

Small-scale studies have found that preschool education can produce sufficiently large effects on the educational achievement of economically disadvantaged children in the United States that it is theoretically possible for it to meaningfully reduce achievement gaps by income and race. However, studies of large-scale public programs tend to find smaller effects that do not persist. Plausible reasons for the disappointing results at scale are the limited quality and intensity of public preschool programs and failure to reach most disadvantaged children so that the schools they enter at age five must still target the needs of the many who do not attend pre-kindergarten. We present analyses for counterexamples that produce large persistent achievement gains in achievement and describe the resources and policies required to transform the quality of early education beginning at age three for the vast majority of children in 31 cities with high concentrations of poverty.