We build and estimate a dynamic model of teenagers’ choices o f schooling and crime, incorporating four factors that may contribute to the differe nt paths taken by different teenagers: heterogeneous endowments, unequal opportunit ies, uncertainties about one’s own ability, and contemporaneous shocks. We estimate the mo del using administrative panel data from Chile that link school records with juvenile criminal records. Counter- factual policy experiments suggest that, for teenagers wit h disadvantaged backgrounds, interventions that combine mild improvement in their schoo ling opportunities with free tuition (by adding 157 USD per teenager-year to the existing high school voucher) would lead to an 11% decrease in the fraction of those ever arrested by age 18 and a 13% increase in the fraction of those consistently enrolled throughout p rimary and secondary education.