The Common Core State Standards (CCSS) emphasize disciplinary literacy by making literacy instruction every teacher's responsibility (National Governors Association Center for Best Practices & Council of Chief State School Officers, 2010). The CCSS require content area teachers to adapt curriculum and pedagogy to support disciplinary literacy development. Therefore, teachers accustomed to stressing only factual knowledge must shift to emphasize the disciplinary learning and thinking that undergirds literacy practices in their subject areas. In addition, they must learn to teach the reading and writing central to their disciplines. In this article, the authors share one school-based effort to support teachers' learning of a disciplinary literacy approach to social studies instruction and what their analysis of student work--one pedagogy used to support teachers--says about their learning. An 18-day U.S. history curriculum designed to teach eighth graders to write evidence-based historical arguments was developed and a 1-year professional development (PD) course for teachers who elected to implement the curriculum was created.