Aim 1a of the project is to evaluate the main effects of the program on both prosocial behavior and substance use. The investigators will also examine effects on secondary outcomes, including delinquent and high-risk sexual behavior, teasing and harassment, depression, school attendance, and academic achievement. The project will include an assessment of program fidelity, which will be incorporated into data analyses. Aim 1b of the project is to explore links among peer rejection, prosocial behavior, and substance use over time in an attempt to determine the direction of effects, which can inform both developmental theory and future intervention design.