The barriers to diversity in computer science (CS) are complex, consisting of both structural and social barriers. In this paper, we focus on social perceptions for students in grades 7-12 in the U.S. using surveys of nationally representative samples of 1,672 students, 1,677 parents, 1,008 teachers, 9,805 principals, and 2,307 superintendents. Building on qualitative work by Lewis, Anderson, and Yasuhara [1,2], we sought to understand social beliefs regarding students' fit and ability as well the external context. We examined these factors' relationships to students' interest. The results are consistent with the current body of research on gender differences in social perceptions in CS. They also identify new findings for race/ethnicity, specifically Black and Hispanic students. As K-12 CS expands, these findings could inform differentiation strategies in equitably engaging students.