Theory suggests that studying worked examples and engaging in self-explanation will improve learning and problem solving. A growing body of evidence supports the use of web-based assessments for improving undergraduate performance in traditional large enrollment courses. This article describes a study designed to investigate these techniques in a practical web-based setting. This study tracked introductory college chemistry students' use of a course quizzing system that provided both worked examples and strategy suggestions embedded within the quiz items. Student perceptions of the effectiveness of the enhancements were measured and correlated to use and performance. The findings indicate students made use of both the worked examples and self-explanation prompts, felt they were helpful, and the interventions improved performance. (Contains 1 table and 7 figures.)