Underrepresentation is endemic across disciplines and across time (National Science Foundation 2019), and extensive research clearly shows that this reflects bias and a lack of access, not a lack of ability in students from those underrepresented groups (National Research Council 2012). Systemic injustice is present in the teaching (Moss-Racusin 2012), learning, and practice (Leslie, 2015) of science, both historically and today. This is a moral problem, and also a pragmatic one. Research has shown that less-diverse scientific groups do less impactful work (Freeman and Huang 2014). Crucially, nobody is better positioned to address these systemic imbalances in science than science teachers. In this article, Moses Rifkin argues educators must help their students see through science how society needs improvement and give them tools to bring it about. But few resources exist for science teachers who want to bring social justice into the science classroom. Herein, Rifkin shares one such resource, the Underrepresentation Curriculum (URC)--a free set of lesson plans and resources, created and curated by science teachers to help fellow science teachers bring social justice to their classrooms--and how he implements it in the classroom.