Gal'perin's instructional theory of problem solving is described. This theory of stage-by-stage formation of mental actions was chosen as a theoretical basis for the construction and evaluation of courses in higher education, particularly in science and technology. A Programme of Actions and Methods (PAM) for problem solving in science, particularly in thermodynamics, was developed, and a system of heuristics was derived from it. Details on the instructional theory, PAM, the systems of heuristics, teaching plans, as well as the main data on the process and product evaluation of the experimental courses are presented. (Author/JN)