Growing evidence indicates that education is associated with health, yet we lack knowledge about the specific educational experiences influencing health trajectories. This study examines the role school factors play in the emergence of poor young adult health outcomes for a low-income, minority sample. The following research questions are addressed. First, what are the education-based predictors of daily tobacco smoking, frequent substance use, depression, and no health insurance coverage? Second, do later-occurring school factors explain the association between earlier school measures and the outcomes and, if so, what pathways account for this mediation effect? Data were derived from the Chicago Longitudinal Study, an investigation of a cohort of 1,539 individuals, born around 1980, who attended kindergarten programs in the Chicago Public Schools. Participants were followed prospectively from early childhood through age 24, and study measures were created from various data sources and multiple assessment waves. Findings from probit hierarchical regressions with controls for early sociodemographic covariates indicated that elementary school socioemotional classroom adjustment and high school completion were significantly and negatively associated with all four study outcomes. Participation in the Chicago Child Parent Center preschool program predicted lower rates of both daily tobacco smoking and no health insurance coverage (p<.05). Middle school reading achievement was inversely related to depression (p<.01), while middle school frustration tolerance was inversely associated with daily tobacco smoking and frequent drug use (p<.05). Also, negatively linked to frequent drug use was a high school measure of students' expectation to attend college (p<.01). In nearly all cases, later-occurring school factors fully mediated significant associations between earlier ones and the outcomes. Patterns of mediation were explored along with implications of results.