This evaluation report describes a program designed to reduce substance abuse among students by establishing a comprehensive peer program in the middle schools (grades 6 through 8). The background of the project is reviewed, five important aspects of a peer helper program are listed, and three intervention strategies of peer assistance programs are discussed: peer management, peer tutoring, and peer helping. The program description focuses on three program features: (1) positive peer influence, peer helper activities, and communication strategies; (2) cross-age teaching activities on drug-specific and other topics to link middle school peer helpers to fourth and fifth grade students; and (3) increased parent involvement. Program goals, staff and resource support, student demographics, curriculum and curriculum materials, cross-grade facilitation, and parent involvement are discussed. A section describing the evaluation study discusses methodology and sampling techniques. An analysis of the findings focuses on program implementation, student attitudes, student achievement, attendance, referrals for assessment, staff perceptions, parent involvement and student perceptions. The conclusion states that the program demonstrated beyond question that the peer helper model offers a unique approach to alcohol and drug prevention in middle schools and has implications for curriculum and student services in general. Five recommendations are given, based on the findings of the evaluation study. Following the references, a set of risk factors for teenage drug abuse, the Peer Helpers Scale, and summaries of scores on the scale are appended. (NB)