Internalizing mental health issues are a significant developmental and clinical concern during adolescence, but rarely identified as a problem among school staff. Using data from the National Longitudinal Study of Adolescent Health, this study examined the associations between adolescent emotional distress, school connectedness, and educational achievement by exploring potential mechanistic and interactive roles of perceived school connectedness on the emotion-education association. Emotional distress was negatively associated with adolescents' perceptions of belonging to school, which, in turn, may negatively influence educational achievement. School connectedness also had both additive and multiplicative interaction effects on the emotion-education relationship. Results support previous evidence of school connectedness as a protective factor for adolescents with internalizing mental health concerns, although much of the work to date has focused on externalizing problems. This study informs our understanding of how, why, and for whom emotional problems influence educational outcomes in light of social support in the school context.