The challenge
Disadvantaged children started school far behind and fell further behind over time.
The case
Between 1962 and 1967, the Perry Preschool in Ypsilanti, Michigan, randomly selected 58 of 123 low-income Black children for two years of high-quality preschool with home visits, and followed both groups for decades. IQ gains faded within a few years, but by adulthood the preschool group had higher earnings, more home ownership and fewer arrests. Economists estimated a return to society of roughly 7–10% a year on the investment.
Why it worked
Early childhood programs can pay off through lasting social and behavioral skills, even when test-score gains fade. The study was very small, so its huge influence on policy rests on careful follow-up rather than scale.
Sources
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