Teenage childbearing is associated with negative outcomes for mothers, their children, and society as a whole. We used data from a nationally representative survey that follows young women over time to explore the relationship between three different measures of academic ability and the likelihood of subsequently experiencing a teen birth outside of marriage. Previous studies have found that girls who perform well in school are less likely to become teen mothers. We show that this is true for some girls, but not for others. We also show that not all measures of academic ability are related to the risk of nonmarital teen childbearing.