Impulsivity holds a central place in the explanations of adolescent delinquency. Recent research suggests that neighborhood characteristics, particularly SES (socioeconomic status), perceived supervision, and collective efficacy, moderate the association between impulsivity and delinquency. However, findings to date have been equivocal, and the relationships between social context, impulsivity, and delinquency remain an open question. This study builds on the current literature by examining the moderating influence of a second context, the high school, on the relationship between impulsivity and delinquency. The authors focus explicitly on self-reported delinquency that has occurred on school grounds, referred to here as school misconduct. Results of hierarchical logistic regression models using the National Longitudinal Study of Adolescent Health suggest that the relationship between impulsivity and two measures of misconduct vary significantly across schools. Moreover, the relationship between impulsivity and weapon carrying is stronger in schools characterized by a limited sense of connectedness among students.