This paper estimates the causal effect of being born to a teenage mother on children's outcomes, exploiting compulsory schooling changes as the source of exogenous variation. We impose external estimates of the direct effect of maternal education on child outcomes within a plausible exogeneity framework to isolate the transmission from teen motherhood per se. Our findings suggest that the child's probability of post compulsory education decreases when born to a teenage mother, and that the daughters of teenage mothers are significantly more likely to become teenage mothers themselves.