An 18-month qualitative study examined the process of designing, developing and evaluating a video-case laserdisc-based instructional support program for the professional development of English/language arts teachers and focusing on the application and practice of the reading/writing workshop approach. The first step was the creation of a prototype of an interactive laserdisc program named Literacy Education: Application and Practice (LEAP), containing 23 mini-cases featuring 3 experienced middle school teachers who use the workshop approach with their students. In the next step, 29 preservice teachers and their professor were observed as they used LEAP for 8 weeks. Data were collected by video-taping and transcribing sessions and presentations, collecting questionnaires, and conducting interviews. Eight groups of 3-4 students selected a book of their choice from the LEAP collection, explored the mini-cases, and prepared a presentation in two 2-hour sessions. Results indicated that the preservice teachers did engage in rich dialogue triggered by the video-cases, the books, and their recollections of classroom experiences. Findings revealed that the majority of students stated that they were not familiar with the approach before LEAP, and the education courses at this field site did not include instruction on the workshop approach. (Contains seven references.) (CR)