This article features highlights from an integrated curricular unit designed to challenge how the gender gap influences young learners' gender stereotypes of STEM professions by allowing students to question their own biases about these occupations while learning herstory. It was implemented in a third-grade classroom in a suburban elementary school in southeastern Pennsylvania. The unit consisted of ten lessons (of 30 to 45 minutes each) taught over the course of two consecutive weeks. Emily Holmberg created the unit to interrupt the traditional ways of teaching both history and STEM by combining the two subject areas while infusing a gender-critical perspective.