Effectiveness of a simultaneous prompting procedure was evaluated for students with mental retardation at different levels of schools (preschool, primary and secondary grades) using various discrete tasks. Participants included three students whose functioning levels ranged from typically developing to mild and moderate mental disabilities. Effectiveness of a simultaneous prompting procedure was evaluated through use of a multiple probe design across behaviors and replicated across students. Results indicated that the procedure was successful in teaching targeted behaviors to all students. Students maintained target behaviors at high rates up to 7, 18, and 25 weeks after training and generalized responses across people, materials, and settings. Limitations and implications for future research are discussed. (Contains 3 figures and 1 table.)