Whereas environmental health education is rapidly becoming a global priority, it still receives little attention in schools. This paper describes a U.S. National Library of Medicine program, aiming to support environmental health education in grades 6-12 in U.S. schools. The program has four components: (1) developing reliable online resources that provide quality environmental health information; (2) creating lesson plans that integrate our resources into the classroom and extracurricular activities; (3) engaging teachers by inviting collaborations and promoting our resources and activities; and (4) conducting educational research that provides a foundation for the other components. The paper describes specific educational resources and activities and grounds them in learning theories from the fields of cognitive psychology and science education.