A research report in Science, Why Peer Discussion Improves Student Performance on In-Class Concept Questions (subscription required), reports that clickers used in the classroom (see clickers in the classroom for a review) can help students arrive at conceptual understanding on their own through the process of group discussion and debate. According to the authors of the study, most instructors report that the percentage of correct answers almost always increases after peer discussion. They go on to say that it has been generally assumed that active engagement of students during discussion with peers, some of whom know the correct answer, leads to increased conceptual understanding, resulting in improved performance after PI.
In this study, students were asked to answer the question a second time after their peer discussion, but also to answer a different, conceptually related question. Neither the correct answer, nor the student responses were shown between questions. The authors conclude that “our results suggest that peer discussion can be effective for understanding difficult concepts even when no one in the group initially knows the correct answer.”
One of their students, quoted in the study says it pretty well: “Often when talking through the questions, the group can figure out the questions without originally knowing the answer, and the answer almost sticks better that way because we talked through it instead of just hearing the answer.”