2. Jigsaw (Aronson, 1978)
Needs Groups of four to five · Grades 2 to 8 · 30 to 45 minutes · The material in four segments
Home groups of four form, and each member takes one segment of the material; expert groups, one per segment, work it together, then the experts go home and teach it, and an assessment covers all four segments. The meta-analysis on it finds a large average effect on achievement, with a caution: the effect shrinks in the larger studies, so read the big number with the asterisk attached (Cochon Drouet, Lentillon-Kaestner, and Margas, 2023, 43 studies). As usually run, though, nothing rides on it beyond the quiz, and there’s no way to tell who taught what.
The fix
- Give the home group a product it can only finish with all four parts.
- On the quiz, ask each student about a segment they didn’t study.






