In this paper we present findings from a study investigating the relationship between all girls' classes, all boys' classes and coeducational classes on student mathematics self-concept and student perception of classroom environment. Further, we compared responses of girls in all girls' classes to girls in coeducational classes and responses of boys in all boys' classes to boys in coeducational classes. Using the Mathematics Attitude Scale and the What is Happening in This Class questionnaire, we found no significant differences in student responses on any of the subscales or domains for any of the subgroups, except for Math as a Male Domain. Our findings indicate that student mathematics self-concept and student perception of the classroom environment are similar regardless of whether students are in a single-sex or a coeducational class. [For the complete proceedings, see ED597799.]