This paper reports on the effects of structuring problem solving activities of novices in the domain of physics in a way consistent with the problem solving approaches used by experts. A total of 42 undergraduate students who completed a first semester physics course and received a grade of B or better participated in this study. The treatment involved five 1-hour sessions during which subjects solved a total of 25 classical mechanics problems using a hierarchical, computer-based, problem-analysis environment called the Hierarchical Analysis Tool (HAT). Two types of tasks were administered before and after treatment: (1) a problem-categorization task; and (2) a problem-solving task. The results indicate that the hierarchical approach to problem solving as exemplified by the HAT helped students to shift their decision-making criteria for problem categorization from one based on surface features toward one based on deep structure. Two implications from this study were discussed. Twelve references are listed. (YP)