Using data on young men from the National Education Longitudinal Survey, this paper investigates the relationship between childhood misbehavior and later education and labor market outcomes. The main finding is that eighth‐grade misbehavior is important for earnings over and above eighth‐grade test scores. Moreover, controlling for educational attainment, childhood misbehavior is associated with earnings at all educational levels, whereas achievement test scores are related to earnings only for young men with postsecondary degrees. Possible explanations for the association between eighth‐grade misbehavior and economic success are explored.