The Mathematics Teacher Development Program was an effort to develop the skills of classroom teachers in the use of handheld calculators and microcomputer systems. It was sponsored by the National Science Foundation and Loyola University, and it consisted of an academic portion and an intense 3-week, full-time summer session. The focus of this paper is a study done during the 1980 summer portion of the program. During this time, the teachers received training in both computer science and computer problem solving in mathematics. The purpose of the study was to assess the effectiveness of this instruction on cognitive and affective objectives associated with computer literacy. Thirty-three teachers were used as subjects. All teachers were female and were placed in two different instructional tracks. Eleven completed track 1, and 22 completed track 2. Track 1 teachers were taught various topics in discrete mathematics, while those on track 2 were instructed in aspects of linear algebra and matrix theory. The investigation focused on 15 days of intensive summer instruction that involved microcomputers. Results indicated that the summer program had a positive effect on the computer literacy of teachers. (Author/MP)