Deaf students are under-enrolled in science, technology, engineering, and mathematics (STEM) majors, making it important to explore how and why deaf and hard of hearing (DHH) students connect (or fail to connect) with STEM. Engaging students in informal STEM with attention to how such experiences interact with their identities has the potential for broad impact on supporting DHH adolescents' entry into STEM areas of postsecondary study and later into STEM careers. We explored the intersectionality of DHH minority racial/ethnic high school students' identities and how it relates to their connection to STEM during a summer program and throughout the following school year. We report on three case studies, followed by a cross-case analysis. Participants were DHH high school students from underrepresented minority racial/ethnic groups. Our case studies were of one female and two male students. Data sources included a battery of surveys assessing scientific sensemaking, affinity toward STEM, and reading ability, as well as a focus group during summer STEM camp, individual interviews the following school year, and observations of photographs taken during camp by volunteers working at the camp. We pinpoint instances of connection to and disconnection from STEM in our three cases. Cross-case analysis implicates a need for applied learning opportunities that overcome language-related barriers for American Sign Language (ASL) users. They also suggest a role for STEM-relevant mentorship that is sensitive to adolescents' intersectional identities, particularly employing adult mentors with whom adolescents can identify. Finally, findings suggest that adolescents are attempting to connect STEM with their everyday lives, particularly their career aspirations. Importantly, our three cases were better able to apply STEM to the real world and career goals in an informal summer STEM camp than in their formal science, math, and engineering classrooms. We discuss implications for curriculum, instruction, and teacher preparation.