The Abecedarian study was a randomized controlled trial that provided full-time, high-quality early childhood education to 111 infants from low-income families in North Carolina between 1972-1977. Children were randomly assigned to a treatment group that received educational childcare from infancy through age 5 or a control group. The study found that children in the treatment group scored significantly higher than the control group on tests of cognitive development by age 18 months and maintained this advantage through age 8, demonstrating the powerful impact early education can have on child development.