This book examines research and public policy regarding single-sex schooling, particularly girls-only classes in public, coeducational schools. The book explains that since the passage of Title IX in 1972, which calls for equal access and participation regardless of gender, educators have attempted to address gender equity issues in schools. It contends that current research on the progress of female students in U.S. public schools suggests that efforts have not sufficiently addressed concerns such as academic underachievement in the areas of mathematics and science, lower self esteem from the advent of early adolescence, and vulnerability to sexual harassment. Despite Title IX, some educators have turned to the creation of single-sex classes and programs for female students to address these critical issues better. The book examines the longitudinal results of one study, reviews other research, and considers policy implications in conflict with Title IX. Contains 91 references. Appendices present teacher and student protocols from public and private schools. (BT)