We describe a systematic study of skills for solving problems in basic physics, a domain of practical significance for instruction, but not of prohibitive complexity. Our studies show that an inexperienced student tends to solve a problem by assembling individual equations. By contrast, an expert solves a problem by a process of successive refinements, first describing the main problem features by seemingly vague words or pictures, and only later considering the problem in greater detail in more mathematical language. We have formulated explicit theoretical models with such features and have supported them by some detailed observations of individuals. In addition, experimental instruction incorporating such features seems to improve problem‐solving performance significantly. These investigations yield thus some basic insights into thinking processes effective for problem‐solving. Furthermore, they offer the prospect that these insights can be used to teach students improved problem‐solving skills and to modify common teaching practices which inhibit the development of such skills.