Many students, and a particularly high proportion of females, do not study mathematics beyond minimum high school requirements. Research indicates that segregation of mathematics classes may help reduce the incidence of female students dropping out of that subject. To improve female students' attitudes toward mathematics and to increase the enrollment of females in upper level mathematics courses, students enrolled in grade 10 and 11 at A. Y. Jackson Secondary School were placed in sex-segregated math classes. This study focused on four main areas: attitudes, achievement, enrollment, and perceptions of the program. The longitudinal analysis of attitudes toward mathematics for students who were grade 11 in 1985-1986 provided some evidence that segregated classes had a beneficial effect on female students' attitudes. The analyses of data regarding student achievement and enrollment in mathematics are discussed. The majority of teachers thought that segregation created a more relaxed and open atmosphere. Comments made by parents reflected that attitudes and achievement were not affected by segregated classes, but that student ability or motivation and teacher's competence were important factors. Students surveyed felt more comfortable and relaxed and less intimidated in segregated classes. Appendices include student and parent questionnaires, interview materials, statistical tables, and responses to the questionnaires. (YP)