Two staff members working in different preschools received training in the form of instructions, modeling, immediate feedback, and social reinforcement of good performance. Effects of training were assessed with a multiple baseline ABCDCDCD design. Correct use of basic behavioral teaching techniques increased from 16-31% to 92-95% and the rate of learn units increased from 0-0.03 to 2.3-2.4 per minute. A multiple baseline design revealed skill improvements in two 2-year-old boys with developmental disabilities. Skills of instructors and children generalized across teaching settings. Follow-up measures showed maintenance and additional generalization of skills. The results confirm the positive effects of increased rate of learn units on teaching effectiveness and students' skills, and the importance of high achievement criteria for generalization. (Contains 3 tables and 6 figures.)