The present study investigated pathways that might explain the observed linkage between participation in early intervention programs and later educational attainment using a sample from the Chicago Longitudinal Study, an on-going investigation of low-income minority children growing up in high-poverty neighborhoods in Chicago. A review of literature on pathways of early intervention programs on educational attainment was provided. Five mechanisms derived from previous studies, i.e., cognitive advantage, family support, social adjustment, motivational advantage, and school support, were investigated as predictors of educational attainment at age 22 years. LISREL analyses revealed that the relation between participation in the Chicago Child-Parent Center (CPC) program in early childhood and subsequent educational attainment was best predicted by cognitive advantage effects, followed by family support and school support effects. The findings indicated that environmental factors, such as family and school, as well as personal characteristics that may be affected by the intervention, play important roles in predicting educational outcomes. The discussion focuses on how environmental factors such as promoting family-school partnerships and attention to family influences in early intervention programs might maintain and enhance the effects of early intervention so as to promote higher educational attainment much later in development.