Asthma education interventions primarily target young children and adults, and a few target adolescents. Several constructs of the social cognitive theory were used to design a classroom-based high school asthma education curriculum and to determine if the curriculum would improve asthma knowledge and attitudes among 10th grade students, as well as improve the quality of life, self-efficacy, and self-management behaviors among asthmatic students. Using a nonequivalent control group design with delayed intervention (three-week delay) in one group, we surveyed a sample of 122 10th grade health academy students. Twenty-four students (20%) reported having doctor-diagnosed asthma. Statistical data analysis determined that asthma knowledge mean scores and self-efficacy mean scores significantly improved for students who received the curriculum. Most students held favorable attitudes towards asthmatics before the intervention, with a slight decrease in positive attitudes after the intervention. There were also slight, insignificant improvements in quality of life among asthmatic students. This study demonstrated that the asthma curriculum improved knowledge among asthmatic and non-asthmatic students and self-efficacy among the asthmatic students. Asthma education, based on a theoretical framework, can be effectively incorporated into a traditional high school curriculum. (Contains 2 tables.)