This study examines relations among antisocial and prosocial activities for boys and girls aged 10, 12, and 14 years. Antisocial activities included substance use and other deviant behaviors. Prosocial activities included physical activity, organized sports, organized nonsport activities, volunteer and religious activities. Household income and single-parent vs. two-parent family status were included as covariates. The sample comprised 356 youth (mean age = 12.06 years, 50% female, 73% White). A six-group (Age × Gender) multiple-sample structural equation model was employed to determine the existence of latent factors (substance use, deviant behaviors, prosocial activities) and relations among variables. Results showed a positive relationship among prosocial behaviors, and between substance use and other deviant behaviors. Organized sport and days of physical activity were inversely related to substance use. Higher income and living in a two-parent family were associated with less substance use and deviant behavior. There was little variation by gender and age.