This case study evaluates a field-based strategy for training in-service elementary teachers to use technology. The strategy, which was incorporated into the Long Beach Professional Development School for Educators (LBPDSE), involved a technology course taken by a cohort of students in an on-site M.A. program in Curriculum and Instruction. Participating teachers identified topics of interest and, in teams, taught one another both computer and technology integration skills. Data were collected including beginning-of-course and end-of-course professional development plans and self-assessments, plus post-course focus group meetings. Prior to the course, teachers' predominant uses of computers were largely peripheral to their subject matter instruction, and their beginning-of-course self-assessments of their technological skills were mostly at introductory proficiency levels. By the end of the course (a) teachers began applying many of the introduced technology integration skills to their teaching, (b) most teachers' technology self-assessments reached intermediate to advanced proficiency levels, (c) the most frequently mentioned means for further professional development in technology was learning from fellow teachers, (d) over one-half of the teachers reported increased confidence or comfort with computers, and (e) about one-third of the teachers reported a substantial shift in their stance towards computers.