The purpose of this paper is to outline the evaluation plan for the Minnesota D.A.R.E. Plus Project, a drug and violence prevention program for young adolescents, and to present the results of psychometric analyses on the measures that will be used in the assessment of the intervention program. The survey instrument was tested using different samples for each stage of its development. The main scale development sample included seventh grade students in urban, suburban and rural schools. The results indicate that the scales constructed are reliable and valid measures of young adolescents' drug use and violent behaviors, as well as intrapersonal, social, and environmental factors related to those behaviors.