New perspectives and techniques are shaping the field of computer-aided instruction. These essays explore cognitively oriented empirical trials that use AI programming as a modeling methodology and that can provide valuable insight into a variety of learning problems. Drawing on work in cognitive theory, plan-based program recognition, qualitative reasoning, and cognitive models of learning and teaching, this exciting research covers a wide range of alternatives to tutoring dialogues.William J. Clancey is Senior Research Scientist at the Institute for Research on Learning, Palo Alto. Elliot Soloway is Associate Professor at the University of Michigan.Contents: Artificial Intelligence and Learning Environments, William J. Clancey, Elliot Soloway. Cognitive Modeling and Intelligence Tutoring, John R. Anderson, C. Franklin Boyle, Albert T. Corbett, Matthew W. Lewis. Understanding and Debugging Novice Programs, W. Lewis Johnson. Causal Model Progressions as a Foundation for Intelligent Learning Environments, Barbara Y. White and John R. Frederiksen.