To improve practical IT education, many Japanese universities are implementing project-based learning (PBL). Although a previous study examined the relationship between educational effectiveness and the scatter of personal characteristics, the relationship between educational effectiveness and the combination of personal characteristics in a team, which is important to optimize the team composition for PBL, has yet to be examined. Herein, we use the five factor and stress theory to measure personal characteristics and classify students enrolled in a PBL class at Waseda University into four types-leadership, management, tugboat, and anchor. Then, knowledge and skills questionnaires are used to measure educational effectiveness. The results show that educational effectiveness is highest when a team consists of management and anchor types without leadership types. The results are preliminary, because the practical usefulness of our results is limited as the experiment of the paper targeted only one PBL course of one university. For that reason, we need to collect data from other PBL course at the same or other university.