Performance by university undergraduates on a microeconomics test after completing an introductory, virtual lecture was preserved after a 12-hour period that included sleep, especially for cognitively-taxing integration problems. In contrast, performance declined after 12 hours of wakefulness and after a longer delay of one week. The study uniquely extends sleep research to a realistic task that students would encounter in a university classroom. The study involved 102 undergraduates who had never taken an economics course.