Over the past several years, the authors have been developing an instructional technology, called Teachable Agents (TA), which draws on the social metaphor of teaching to help students learn. Students teach a computer character, their "agent," by creating a concept map of nodes connected by qualitative causal links. The authors hypothesize that…

Betty's Brain is a computer-based learning environment that capitalizes on the social aspects of learning. In Betty's Brain, students instruct a character called a Teachable Agent (TA) which can reason based on how it is taught. Two studies demonstrate the "protege effect": students make greater effort to learn for their TAs than they do…