Rules and problem solving: another look

College students were trained on problems similar to the water jar problems developed by Luchins (1942). Some students were instructed that a particular rule would solve all the problems, others had the same problems but were not instructed about the rule, and a third set of students had a series of novel problems in which no single rule operated throughout. In two experiments students in the instructed rule group not only performed best in training but also performed best when transferred to a condition in which a single novel rule was appropriate. Although results from the set of conditions most similar to those of Luchins suggested that students sometimes inappropriately persisted in rule usage, the overall results suggest that rigidity is not a necessary outcome of instructed problem solving. Indeed, many of the results were consistent with the notion that instructed problem solving is flexible problem solving.