External support and the development of problem-solving routines

Participants in 2 experiments practiced solving complex arithmetic problems with or without external memory aid (paper and pencil). Participants with the memory aid more often developed routines that corresponded to the conce ptual structure of the task. The availability of a memory aid also slowed t he rate of settling on a stable routine. In Experiment 2, the availability both of an external memory aid and of a worked example varied between parti cipants. Examples had the greatest influence on initial problem-solving str ategies but did not override the effects of the memory aid. The results pro vide evidence about the roles of situational and cognitive constraints in s haping problem-solving routines.