Teamwork is recognized as critical to solving complex societal challenges related to energy, health, and sustainability. With graduate education, students often gain teamwork experience through a problem-focused approach where they are brought into existing collaborations to pursue research that is focused on studying questions that have already been identified. Here, we describe an interdisciplinary educational program where graduate students were tasked with leading team formation, problem identification, and research formulation. This team-first training approach used a two-year curriculum to bring together students enrolled in diverse engineering and science graduate programs and provided students with a pedagogical understanding of interdisciplinarity, nurtured the development of student communication skills across disciplines, fostered student-led team formation and idea development, and empowered students to forge new connections between research groups. Assessment of three cohorts immediately following curriculum completion (n = 36) revealed significant gains in confidence in teamwork (p < 0.001) when compared to a control group of academic peers (n = 74). These gains varied across demographic groups, with women in science, technology, engineering, and mathematics presenting the strongest gains. This finding illustrates the importance of exploring how interdisciplinary team curricula in graduate school could support overcoming the gender gap in confidence.