PURPOSE Many schools engage in health promotion, health interventions, and services aimed at improving the health and well-being outcomes for students. The purpose of this study was to examine the effects of schools on student health risk-taking behaviors and depressive symptoms. METHOD A nationally representative sample (n = 9,056) of students from 96 secondary schools completed a health and well-being survey using Internet Tablets that included questions on school climate, health risk-taking behaviors, and mental health. Teachers (n = 2,901) and school administrators (n = 91) completed questionnaires on aspects of the school climate which included teacher well-being and burnout, the staff work environment, health and welfare services for students, and school organizational support for student health and well-being. Multilevel models were used to estimate school effects on the health risk-taking behaviors and depression symptoms among students. RESULTS Schools where students reported a more positive school climate had fewer students with alcohol use problems, and fewer students engaging in violence and risky motor vehicle behaviors. Schools where teachers reported better health and welfare services for students had fewer students engaging in unsafe sexual health behaviors. Schools where teachers reported higher levels of well-being had fewer students reporting significant levels of depressive symptoms. CONCLUSIONS More positive school climates and better school health and welfare services are associated with fewer health risk-taking behaviors among students. However, the overall school effects were modest, especially for cigarette use and suicidal behaviors.