This report summarizes an evaluation of a staff development program to reduce disparity in educational achievement across race and sex. The Teacher Expectations and Student Achievement (TESA) program of S. Kerman, T. Kimball, and M. Martin (1980) was implemented in an elementary school. Achievement test scores, attitudes toward school and self, perceptions of teacher practices, and grade retentions were compared for the 306 students of teachers who volunteered to participate in the experimental program and students in the same school (n=329) and in a different school (n=250) whose teachers did not participate. The results differ depending on which comparison group is used. A small positive effect is implied by the within-school comparison, and a negative effect is implied by the between-school comparison. Because of competing explanations, the results remain ambiguous. In view of the popularity of the program, the limited prior empirical support for its usefulness, and the ambiguity of the results, it is concluded that further studies that include randomized trials and more careful records of the level of implementation are required. Statistical data are provided in 11 tables and 2 figures. There are 26 references. (Author/SLD)