Four self-instructional modules designed at the City University of New York for training special education teachers were field tested with 357 students. Information on module functioning was obtained from students and instructors through questionnaires, ratings of module activities, comments on the materials and problems encountered, and observations of students participating in module activities. Instructors who took an active role in the module reported a greater success rate than those instructors who didn't take an active role. Among the module adaptations made by instructors to meet student needs were provision of supplementary work assignments where needed and use of students' prior experience. Field testing revealed the difficulty in developing valid pre- or postassessment procedures. (SB)