Knowledge of the importance of mediating processes for sustaining performance, and of self-organizing abilities for learning to perform a given task, served as the basis for a method (called TASKTEACH) of using a time-sharing digital computer to assist learning of prescriptively-guided or problem-solving serial-action tasks. The students involved in this program are provided with instruction in different mediating processes and their corresponding requirements and with a variety of types of support: explicit maps of task structures, control of procedure, control over monitoring progress, explanations of computer responses, suggestions for the next action, and a detailed history of all actions accomplished and errors committed. These support functions are implemented singly, in standard combinations, or in individually tailored combinations determined by the student. Combinations are arranged with the support functions to form four modes of support, each characterized by a particular pattern of support functions (ranging from maximum support to none at all) which are automatically provided in that mode. TASKTEACH is currently undergoing field tryout and is expected to encourage the generalization of self-organizing abilities, to facilitate the learning of mediating skills, and to increase learning motivation. (Author/SP)