We develop a Roy model of social interactions in which individuals sort into peer groups based on comparative advantage. Two key results emerge: First, when comparative advantage is the guiding principle of peer group organization, the effect of moving a student into an environment with higher-achieving peers depends on where in the ability…

Highlights the importance of the dynamics of the learner group in shaping the second language (L2) learning process, and overviews the most relevant aspects of classroom dynamics. Argues that group characteristics and processes affect any success or failure in the L2 classroom and that teachers could benefit from an awareness of the principles of…

Provides observational behavioral and ethnopsychological data from 15 Japanese nursery schools, intended to identify potentially interesting areas for future research on nursery schools and to stimulate American thinking about school practices which influence development of cooperative behavior in children and adult strategies for controlling…

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…