The first volume of a two-volume report on the study of sex equity in classroom interaction presents findings of previous studies of classroom interaction, methods used in the study, observations of classroom interactions, possible causes of sex segregation, sex differences in classroom leadership, and intervention implementation effects. The final chapter presents a summary of results. The two-year study (1980-82) involved 38 fourth- and fifth-grade classrooms in two districts in California and Connecticut. A total of 356 boys and 359 girls served as target students during the first year and 132 boys and 139 girls served as target students during the second year. Over 8,500 student hours of observation were augmented by in-depth interviews with teachers who participated in the study. In addition, an APPLE observation system was used as the study's major tool for observing and preserving classroom processes for analysis. Data from the study do not support the notion that classroom teachers play a major role in creating and maintaining inequities. Despite findings that boys are more disruptive (and thus receive more teacher attention), data suggest that teachers respond to the nature of the student behavior rather than to student gender. Findings concerning peer interaction showed that despite an overwhelmingly strong same-sex preference on the part of both girls and boys, students actually engaged in cross-sex interaction quite frequently and with no observable consistent differences from same-sex interaction. (LH)