This study used a novel approach to examine the link between gender ability stereotype endorsement and academic interests by examining not only stereotypes people hold "within" the domains of mathematics and language arts, but also "between" them. Grade 6 and 8 students (285 males, 363 females) reported their degree of stereotype endorsement and interest in these two academic domains. Results of path analyses revealed that stereotype endorsement within and between domains accounted for gender differences in interest. In language arts, endorsing a stereotype that females are more competent than males predicted subsequent interest in the domain and accounted for the greater language arts interest among females. In mathematics, however, the perception that males are more competent in mathematics relative to language arts was linked to students' interest in this domain and accounted for the interest gap between genders. These results suggest that students' interests relate to endorsed stereotypes that are either driven by a perceived gender superiority "within" one domain--when females are viewed as more competent than males in language arts--or a gender superiority "between" two domains--when males are viewed as more competent in mathematics relative to language arts. Considering not only stereotypes favoring a gender within one domain, but also between domains, provides a more accurate portrait of students' actual stereotypes and can be useful to better understanding how the interest gap emerges.