Components of a computer solution for fraction problems in arithmetic have an analog in a new approach to educational task analysis. The components may be called goal-setting or planning elements, in contrast to the goal-satisfying or behavioral steps emphasized in much contemporary task analysis. A hypothetical tutorial dialogue in which a student is asked to tell a tutor what step to perform next is presented as an example of the emphasis of the planning side of computation. Explicit identification of goal-setting elements of a task is illustrated by analysis of the task of converting a pair of fractions to a new pair with a common denominator. The decomposition thus produces is simulated with two computer programs: (1) a LISP program using a set of production rules consisting of conditions to be met and subsequent actions to be taken and (2) a PROLOG program stating goals and solving goals explicitly. © 1981 Psychonomic Society, Inc.