The snowball survey and peer education posters: methods of teaching social norms.

Adolescent substance use is a major health issue in the United States. Adolescent substance use is associated with motor vehicle crashes,1 risky sexual behaviors,2 and the development of substance disorders during adulthood.3 National studies indicate that the use of alcohol, tobacco, and other drugs (ATOD) among adolescents attending high school has declined considerably since the early 1990s.4 However, within the past few years, reductions in ATOD use have slowed to moderate or insignificant levels,4 an issue requiring the focus of health professionals.