This research describes an observation study of 100 children, ages 9-13 years, on the island of 'Ua Pou, Marquesas Islands, French Polynesia. The children were in a French government boarding school in the main valley of the island. Complex, sophisticated group processes among the Marquesan children were observed. The role structures of the group are explained and roles are seen to fit together to produce coordinated group action. The process of starting a large group game is used to illustrate the points of group dynamics. Marquesan peer dynamics are found to differ greatly from the interpersonal dynamics children come in contact with in their formal French schooling. Polynesian children have been found to spend much time together in unsupervised peer groups. They also teach each other major lessons about how to get along with others. (EH)