The connection between high school courses and student knowledge on standardized tests has seldom been studied in social studies fields—and almost never on a national basis and with a wide range of statistical controls. We look at the relationship between course work in U.S. history and performance on the 1994 National Assessment of Educational Progress (utilizing the 1994 High School Transcript Study to measure course enrollments). We find that students who take more and higher-level course work, who reported greater emphasis on a broad array of historical topics, and who experienced more “active” instruction performed better on the NAEP test even after adjusting for numerous student and family characteristics. The findings provide support both for increasing the amount of history course work and for enlightened instructional practices.