This paper examines how two dimensions of childhood religion affiliation and participation are related to the probability of graduating from high school. Hypotheses derived from a human capital model are tested with data on non-Hispanic white and black women from the 1995 National Survey of Family Growth. The empirical findings are generally consistent with the hypotheses, revealing sizeable differentials in the likelihood of obtaining a high-school diploma by affiliation and participation. The results suggest that the convergence of Catholics to the mainline Protestant pattern for non-Hispanic whites found here, and supported by many previous studies, has not taken place in the black population. In other respects, the relationships between religion and high school graduation are similar for the two racial groups.