The Delaware Geography-Health Initiative is a Web- and GIS-based set of lesson units for teaching geographic concepts and research methods within the context of the state's high school geography standards. Each unit follows a research-based, inquiry-centered model addressing questions of health because of Delaware's high incidence of cancer, HIV/AIDS, and infant mortality. Topics focus on cancer and the environment, the geography of HIV/AIDS, the diffusion of West Nile fever, provision of emergency ambulance services, the location of the state's next hospital, infant mortality and the location of prenatal care, and identification of healthy places. Results from piloting and early formative assessments were used to modify the final product. Lessons learned in developing this project may assist those seeking to create GIS-based state-specific teaching units for geography and other related subjects. (Contains 3 tables and 5 figures.)