This study explored the cognitive responses of adapted physical education teachers during lesson planning. The focus was to determine whether expert (n=4) and novice (n=4) teachers varying in experience and expertise differ in the information they need to plan a lesson and how they conceptualize a lesson. Subjects were given information about a fictional class of handicapped students and were asked to plan a lesson. After writing a lesson plan, they were asked to explain it to the experimenter. The results provided clear evidence of the experienced teachers’ superior knowledge base and repertoire of teaching strategies. Their responses were filled with contingency plans based on the actions and abilities exhibited by the students. In contrast, the novices generated plans that were unidirectional and failed to accommodate the range of ability levels in the class.