This paper presents the results of an evaluation study of a sex equity program designed to affect the achievement and attitudes of early adolescent students in the middle school. The Self-Concept and Decision-Making Middle School Curriculum Program at Florida State University developed sex equity curricular materials titled "Decisions About Roles" that can be infused directly into the middle school curriculum of math, science, language arts, physical education, and social studies. To determine the effectiveness of the program, both formative and summative evaluation procedures were used over two years. During the formative evaluation of the first year, all materials were field tested and student pre- and posttests were administered. The materials were revised as a result of the feedback. The summative evaluation of the second year employed a pre- and posttest design to contrast the gain scores of the students participating in the program (experimental group) and those not exposed to the materials (comparison group) for five dependent measures. Six hundred and thirty students in grades six, seven, and eight at two experimental site schools and 234 students in the comparison school participated. Evaluation instruments administered are described in the paper. Results indicated that the program which includes a substantial social studies component had a significant effect on pupils' achievement, sex-role perceptions, and decision making. Participants made achievement gains in content areas; gained more egalitarian perceptions of occupational, school, and family roles for females and males; expressed more androgynous self-concepts (girls only); and gained confidence in decision making. (Author/RM)