This paper describes AI/LEARN, an educational videodisk system designed to teach clinical observational skills and reasoning in medicine. The AI/LEARN system uses a learning conditions approach to teaching. To teach visual concepts, we use the principle of exemplar/nonexemplar pairs and immediate feedback. To teach If-Then problem solving we use the format of minicases with delayed feedback. The software to operate the system has been custom developed and is domain independent. The result is a prototype of a new authoring package for videodisk teaching which operates on IBM compatible microcomputers. The medical domain selected for this prototype system was rheumatic diseases; the knowledge used to teach reasoning skills is derived from the knowledge base of an expert system: AI/RHEUM.