This article describes how two instructors used assessment data to improve an undergraduate course, Teaching Social Studies in the Elementary Classroom. This entailed revising the core assignment for the course--the creation of a thematic unit of instruction--and developing a scoring guide to assess teacher candidates' performance. Data collected from the administration of the revised thematic unit assignment allowed the instructors to see specific areas where candidates experienced difficulty as they sought to design effective social studies instruction for elementary school students. As a result, the instructors made changes in the course assignment, as well as in their teaching, to improve candidate learning. (Contains 5 tables.)