In cooperative learning, students work together as a team to maximize the academic success of all the team members. The failure of even a single member can compromise the success of the entire team. Thus, to evaluate the functioning of the team reliably, it is necessary to consider both the performance of the individual team members and the interactions among them. In this study, a method was developed for identifying dysfunctional teams and troubled individuals by examining the correlation between the team scores obtained in sequential tests and the correlation between the scores obtained by the different team members. The effectiveness of the proposed method was evaluated via field experiments. Forty‐eight students were randomly assigned to cooperative learning teams and their learning performance assessed by four‐unit tests. The results indicated that the proposed method can identify the most troubled individuals in a team even when the team performance/grouping information is not taken explicitly into account. Furthermore, when the team information is considered, the method can identify both the dysfunctional teams and the troubled individuals within the teams. Therefore, the proposed method provides a useful basis for the development of computer‐assisted solutions for assessing the performance of cooperative learning teams.