In recent decades, many researchers have studied the importance of group-level cognition. Indeed, to my mind, there is now convincing evidence that group activities improve the intelligence of individuals. In this essay, I shall examine how research in team-games and study-groups supports this view. To begin with, team-games clearly require individuals to perform a diverse range of rapid mental calculations. This is because, in a sporting context, players must predict and anticipate possible actions within tight time constraints. For example, a recent Cambridge study showed that soccer players can - within the span of seconds - calculate over a dozen different permutations that could result from a single soccer related action. Such predictive powers clearly improve players' mental abilities and result from activities performed in a group context. Secondly, study-groups enable individuals to obtain information that they could not acquire in isolation. This is because peer feedback allows individuals to refine their understanding of concepts and to also learn new information from other members in the study-group. For example, a study by The British Institute for Learning found that, if individuals participated in study-groups, they had a far more objective and sophisticated understanding of a topic than learners who were not part of study-groups. Therefore, it is certainly the case that learning in a group improves an individual’s mental abilities. In conclusion, I strongly agree with the notion that group activities improve intellectual abilities. In the future, we will certainly see schools take greater measures to ensure that more group-level cognition occurs in the classroom.