The far-reaching consequences of failing to complete secondary schooling are well known. The central questions addressed in this study are: Does religion make a difference in the likelihood of successfully completing the transition to high-school graduation? If so, how large are the influences? Based on a human capital framework, the paper develops hypotheses about the effects of two dimensions of religion during childhood – affiliation and participation – and tests them with data on non-Hispanic white, African-American, and Hispanic female respondents from the 1995 National Survey of Family Growth. The results are generally consistent with the hypotheses, revealing sizeable differentials in high-school graduation rates by affiliation and participation. The results also uncover pronounced differences by race/ ethnicity.