The authors examined experimentally whether student gender and socioeconomic status (SES) affect teachers' expectations of students. Participants were 106 teachers who read a scenario about a hypothetical student with academic and behavioral challenges. The authors systematically varied the gender and SES of the student to create 4 conditions. Teachers rated high-SES boys more favorably than low-SES boys, but low-SES girls more favorably than high-SES girls. Teachers perceived that low-SES students have less promising futures than do high-SES students. Findings suggest that teachers are likely to develop negative attitudes toward low-SES students in general, but especially boys. These preconceived attitudes may help explain why teacher efficacy tends to be lower in economically disadvantaged schools. (Contains 1 table.)