Group differences in the effects of the expectancies and values that high-ability students have for science and mathematics on plans to persist in science, technology, engineering, and mathematics (STEM) were investigated. A nationally representative sample of ninth-grade students, the High School Longitudinal Study of 2009 (HSLS: 2009; n = 21,444) was used. The analytic sample was 1,757 (48% female, 52% male) Black (13.8%), Hispanic (26.7%), and White (59.6%) students who scored in the top 10% of their race group on the mathematics achievement test. Hierarchical logistic regression models were developed for each race/ethnicity group to examine the relationships of demographic and expectancy-value variables with STEM persistence status. Science attainment value, science intrinsic value, and STEM utility value were predictive of STEM persistence, but these variables operated differently in groups of Black, Hispanic, and White students. Implications for educators include the need for ways to improve perceptions of science identity and awareness of the utility of science and mathematics courses.