Abstract : Progress is reported on four research tasks. An experiment was designed to test the effectiveness of our computer-based phonology instructional system for second-language learning, using Spanish-speaking students with English as the target language. In research on models of human-computer interactions, experiments were performed demonstrating that the provision of certain incentives to the users of a time-sharing system can have the effect of shaping patterns of user-choice behavior which improve the overall efficiency of the system. The investigation of programming languages as a tool for cognitive research has led to the development and construction of a wireless computer-controlled vehicle to aid students in conceptualizing previously abstract processes in problem solving. In addition, an experiment was conducted in teaching the programming language LOGO to a group of hard-to-teach students, and the validity of standard measurements of achievement level was investigated. Studies of human memory and language processing have further elucidated the cognitive operations involved in the storage, retrieval, and utilization of factual material.