We introduce contraceptives and social norms in an overlapping generations growth model of fertility and human capital. Parents can use costly modern contraceptives to control their family size, and each household’s fertility decision is influenced by the decisions made by others. Given the number of children born, parents decide how much education to provide and how much to save out of their income. We characterize the local dynamics of a stable steady-state equilibrium. Around this steady state, family planning interventions, which reduce the price of modern contraceptives, decrease fertility and increase human and physical capital. The effects of family planning interventions are larger when reproductive externalities are stronger.