This article describes an attempt to bring disciplinary historical inquiry into the social studies classroom. This work emerges from a five-school 6-month intervention in San Francisco, "Reading like a Historian", which found main effects for student learning across four quantitative measures: historical thinking, factual knowledge, general reasoning, and reading comprehension. The purpose here is to describe the pedagogical practices that were at the heart of the intervention; in particular, a lesson structure that is called the "Document-Based Lesson". The Document-Based Lesson organized existing forms of social organization that typify social studies classrooms (e.g. lecture, recitation, seatwork, group-work, whole-class discussion), into a predictable and repeatable sequence that engaged students in the processes of historical inquiry. Rather than uproot the conventional norms and structures that define classroom behaviour, this study preserved the traditional role of the teacher and the signature activities that stand as landmarks of social studies instruction. Moreover, by providing classroom-ready materials and activities that married content knowledge and disciplinary inquiry, the Document-Based Lesson attempted to reconcile the fundamental tension in history instruction between depth and coverage. (Contains 2 notes and 7 figures.)