We evaluated the effects of participation in an extended program of compensatory education for 559 low-income, inner-city African American children up to seventh grade. The intervention is the federal and state-funded Chicago Child-Parent Center and Expansion Program, which began in 1967. Groups included 426 children who participated in the program from preschool to grades 2 or 3 and 133 children whose participation ceased in kindergarten. After taking into account initial differences in achievement at kindergarten entry and at the end of kindergarten, and after taking into account sample selection bias, program participation for 2 or 3 years after preschool and kindergarten was associated with significantly higher reading achievement up to seventh grade and with lower rates of cumulative grade retention and special education placement (4 to 5 years postprogram). Children participating in the follow-on program for 3 years had significantly higher reading achievement in seventh grade and a lower rate of grade retention than 3 year participants. Only 3 year participants had significantly higher math achievement than the comparison group. Study findings provide rare longitudinal evidence of the beneficial effects of a large-scale community-based program of extended early childhood intervention.