In simple rule-switching tests, 3- and 4-year-olds can follow each of two sorting rules but sometimes make perseverative errors when switching. Older children make few errors but respond slowly when switching. These age-related changes might reflect the maturation of executive functions (e.g., inhibition). However, they might also reflect…

Using data ("n" = 3,790 with 2,119 in the 3-year-old cohort and 1,671 in the 4-year-old cohort) from 353 Head Start centers in the Head Start Impact Study, the only large-scale randomized experiment in Head Start history, this article examined the impact of Head Start on children's cognitive and parent-reported social-behavioral outcomes…

Children from low-income families benefit remarkably from exposure to compensatory education that began with Head Start in 1965 and aimed to improve school readiness skills by design. While empirical evidence has supported more instructional time in elementary and secondary schools for low-income students, little is known that whether increasing…