While participating in single- and mixed-gender science and mathematics classes, ninth-grade urban high school students' (n = 118) academic self-concept, self-efficacy, and school climate perceptions were examined. Their perceptions were measured quantitatively from the Fennema-Sherman Mathematics (modified for Science) Attitude and the Patterns of Adaptive Learning scales. Five factors arose from each instrument: confidence/efficacy, utility, instruction, climate, and anxiety/performance avoidance. Comparative factor analysis of the science-modified Fennema-Sherman Scale showed similar constructs within the mathematics scale. Our findings are congruent with reports concerning single-gender classrooms that find few significant differences in students' attitudes toward science and mathematics, or classroom climate, with regard to single-gender classes. Lastly, our results supported three structural equation models for the hypothesized factors from each instrument.