The research described in this paper leads to an instructional design approach which is an alternative to the consideration of such issues as mathematical skills or level of cognitive development. The approach uses an analysis of traditional instructional tasks to specify the underlying cognitive processes and structures necessary for the successful completion of the tasks; that is, a cognitive analysis of instructional tasks, rather than a logical analysis, is used to arrive at appropriate instructional goals. The approach involves taking a standard form of a question and converting it to a qualitative problem. Appropriate levels of existing relevant knowledge and experience are then determined, and a series of questions and specific, single-observation laboratory exercises are used to gradually develop a schema for the problem solution. The interaction implicit in the strategy allows for the retention of appropriate aspects of existing schemata and the modification of conflicting aspects. Two broad aspects of differences between physics experts and novice physics students relevant to physics problem solving are considered in the approach. These aspects come from recent cognitive psychology research into processes and structures used by experts and novices in physics problem solving and from science education research into student world views. (JN)