Research on intelligent tutoring systems is discussed from the point of view of providing moment-by-moment adaptation of content and form of instruction to the changing cognitive needs of individual learners. Implications of this goal for cognitive diagnosis, subject matter analysis, teaching tactics, and teaching strategies are analyzed. (Author)

Discussion of how visual analogies aid students' understanding of math and science focuses on new types of representations that use computers. Topics addressed include understanding and cognitive performance; the role of representations in understanding, including examples; evidence of instructional effectiveness of new representations; and…

Discussion of computer simulations used for exploratory learning focuses on the design of a hypothesis scratchpad that students can use for hypothesis generation and testing. An experiment with college chemistry students that compared three versions of the scratchpad is described, and the effect of the scratchpads on learning environments is…