TY - JOUR AB - I study whether peer-family health composition affects adolescent risk environments, school relationships, and mental health. Using nationally representative data from the China Education Panel Survey, I exploit quasi-random variation in the share of a student's middle school classmates whose parents report that they never smoke and never drink. A one-standard-deviation increase in exposure to classmates from non-smoking and non-drinking family environments reduces the likelihood that the homeroom teacher reports smoking or drinking among students in the class by 8.2 percentage points. This estimate is concentrated among classmates whose mothers never smoke and never drink. The same peer composition measure is also associated with fewer mental health problems, with larger effects for girls, and with stronger classroom integration, school attachment, and relationships with classmates and teachers. These results suggest that parental health behaviors may generate spillovers beyond the household by shaping the classroom environments in which adolescents form relationships, norms, and behavioral risks. AU - Jiang, Renyu PY - 2026 ST - Parental Health Behaviors Spill Over Through Peers to Shape Risk Environments and Adolescent Mental Health TI - Parental Health Behaviors Spill Over Through Peers to Shape Risk Environments and Adolescent Mental Health UR - http://www.edworkingpapers.com/ai26-1524 ER -