Many bright, talented girls from populations traditionally underrepresented in Science, Technology, Engineering, and Mathematics (STEM) are underachieving or disengaged in school, despite having an interest in STEM. Qualitative research was conducted with teenaged girls from culturally and academically diverse backgrounds participating in an extracurricular scientific diving SCUBA program. The program provided opportunities for these girls to learn and apply STEM knowledge and SCUBA diving skills during research, service learning and place-based, hands-on projects. Findings suggest that motivation for STEM in teenaged girls increases when they are able to participate in real-life, place-based activities they find personally meaningful with other interest-based peers and mentors.