Students work in small groups to develop knowledge about a given topic and to formulate effective ways of teaching it to others. These 'expert' groups then break up and students move to new 'jigsaw' groups, each one consisting of students who have developed expertise in different subtopics.
'Jigsaw' is helpful in motivating students to accept responsibility for learning something well enough to teach it to their peers. It also gives each student a chance to be in the spotlight. When students assume the role of teacher, they lead the discussion, so even students who are reticent to speak up in class must take on leadership roles.