We use student-level online resource usage data for students in four different introductory accounting courses to explore the impact on exam performance of both student study effort and students' revealed preferences for reading text or watching video lectures. The online learning tool tracks student study choice (read text, watch video, or skip) on a paragraph-by-paragraph level. We match these usage data with student performance on course exams. We find that students who study more material earn higher exam scores than do students who study less material. We also find that students who self-select to do relatively more of their studying through reading text score higher on exams, on average, than do students who self-select to do relatively more of their studying through watching videos. Specifically, holding the overall amount of study constant, a student who chooses to spend the highest fraction of her or his study time watching video mini lectures earns exam scores 10 percentage points lower (six-tenths of a standard deviation) than a student who chooses to spend the lowest fraction of study time watching videos. Our results demonstrate that at least for introductory accounting students, increased study effort does indeed have a positive impact on exam performance. Our evidence also suggests that the highest performing introductory accounting students choose to learn accounting proportionately more through reading than through watching. These results are a reminder that when we talk about using "technology" to help our students learn accounting, the written word is still an important technology. [For the complete volume, "Advances in Accounting Education: Teaching and Curriculum Innovations. Volume 24," see ED661366.]