Students are divided into small groups of five or six each. One student assumes the role of the leader, either assigned by the teacher, as a volunteer, or chosen by the group members. The teacher divides the day’s learning into five or six pieces and gives only that piece to one person in each group. Students study their piece for a few minutes and then get into “expert” groups with others who also have the same piece of information. In the expert group, the students discuss the most important aspects of their piece and how they might best teach it to their peers.
Then the “experts” disband and go back to their original groups where they share their learning. You can learn more about the jigsaw method here.
The jigsaw technique was developed and named in 1971 at the University of Texas, Austin by Elliot Aronson (more info) as a way for students in recently desegregated schools in Austin to interact in the classroom in a way that would reduce suspicion and distrust. Aronson has since written widely on the jigsaw technique, focusing on the benefits of jigsaw for reducing hateful behavior and increasing cooperation in the classroom.
The benefits of the technique clearly extend beyond more positive student interactions.