Heterosexual urban middle school students’ (N = 1,757) stereotypes about gender typicality, intelligence, and aggression were assessed. Students (Mage = 12.36 years) rated Facebook‐like profiles of peers who varied by gender, ethnicity, and sexual orientation. Several hypotheses about how the gender, ethnicity, and sexual orientation of target peers intersect to shape stereotypes were tested. As predicted, a peer's sexual orientation determined stereotypes of gender typicality, with gay and lesbian students viewed as most atypical. As expected, ethnicity shaped stereotypes of intelligence, with Asian American students seen as most intelligent. Gender, ethnicity, and sexual orientation independently and jointly affected stereotypes of aggression. These results demonstrate the value of an intersectional approach to the study of stereotypes. Implications for future research and practice are offered.