<p>This study enhances our theoretical understanding of social cognitive theory (SCT) and social cognitive career theory (SCCT) by examining the interplay between team roles and gender among participants and graduates of the For Inspiration and Recognition of Science and Technology (FIRST) robotics program and their subsequent career trajectories. FIRST participants collaborate in gender-diverse teams to construct robots for annual competitions. This study explored strategies to enhance women’s participation in STEM careers. It also characterized team roles, examined how these roles relate to career choices across genders, and investigated their impact on participants’ self-efficacy. Employing an explanatory sequential design methodology, we collected data through questionnaires from 117 high school students and 290 program graduates, supplemented by in-depth interviews with 15 women participants. Applying Bandura’s and SCCT frameworks, this analysis treats self-efficacy as a multidimensional construct informed by four distinct sources: mastery experiences, vicarious experiences, verbal persuasion, and physiological/affective states. The study indicated that repeated successes (mastery), peers’ observations (vicarious), mentor feedback (verbal persuasion), and the emotional climaxes of competition (affective states) interact to reinforce confidence and sustain STEM aspirations. Our findings reveal that the FIRST program contributes to gender equity by positively impacting both men and women participants, with all participants reporting enhanced self-efficacy. Notably, while women participants demonstrated improved self-efficacy in both internal and external managerial roles, enhanced leadership capabilities in external managerial positions were observed exclusively among men participants compared to their non-participating counterparts. The theoretical contribution expands SCT/SCCT frameworks by examining the relationship between team roles, gender, and self-efficacy.</p>