Harriet R. Tenenbaum and colleagues conducted a meta-analysis to examine results from 71 studies about the effects of peer interaction on learning. To be included in the review, studies had to include a comparison group. Peer interaction was defined as small groups of students working together to achieve common goals of learning. Approaches using more formal training, such as cooperative learning or peer tutoring, were excluded. The majority of the studies were conducted in the U.S. and U.K. and included more than 7,000 children between ages 4 and 18.

Published in Journal of Educational Psychology, their findings suggest that peer interaction was effective in promoting learning in comparison with other types of learning conditions (effect size = +0.40) across different gender and age groups. In contrast, children working in peer groups were not more effective than children working individually with adults. There was also no effect for group size, with findings suggesting that children learn the same amount in groups of two children and in larger groups. Moderator analyses also indicated that peer interaction is more effective when children are specifically instructed to reach consensus than when no instruction is given.

The researchers conclude that although peer interaction does facilitate learning, the conditions and means by which this happens varies and depends on a number of moderating factors. They say the findings indicate that the benefits of peer interaction can be realized by educators if they create opportunities not just for discussion, but also for the negotiation of a shared understanding.