Background: Tobacco use, poor eating habits, and physical inactivity are the modifiable risk behaviors most associated with the leading causes of morbidity and mortality in the United States. Because these risk behaviors are established during adolescence, the nation's schools are uniquely positioned to develop health literacy in students. Purpose: The purposes of this study were (1) to evaluate textbook-based health literacy instruction on the acquisition of health concepts and skills, and (2) to use the Health Education Assessment Project (HEAP) database items to assess changes in the concepts and skills associated with risk behaviors. Methods: The study participants consisted of 669 secondary students. Items were selected from the database to measure students' achievement in concepts and skills related to tobacco, nutrition, and physical activity. Results: Results indicated significant improvements in concepts and skills scores from pretest to post-test in the treatment group when compared to the control group. Discussion: Exposure to health literacy instruction through a comprehensive, health education textbook has a positive influence on the development of concepts and skills that contribute to health literacy. Translation to Health Education Practice: Teachers should provide instruction from curricula that focus on health concepts and skills. Additionally, HEAP database items should be used for evaluative purposes. (Contains 2 tables.)