Background: Melanoma, the most fatal form of skin cancer, is rising at a rate faster than that of all preventable cancers except lung cancer in the United States. Childhood exposure to ultraviolet (UV) light increases the risk for skin cancer as an adult; thus starting positive sun protection habits early may be key to reducing incidence. Methods: We evaluated the US Environmental Protection Agency's SunWise School Program, a national, environmental education program for sun safety of children in primary and secondary schools (kindergarten through eighth grade). The program was evaluated with surveys administered to participating students. An identical 18-question, self-administered survey was completed by students (median age, 10 years) in the classroom before and immediately after the SunWise educational program. Results: Surveys were completed by students in 40 schools before (pretests; n = 1894) and after the program was presented (post-tests; n = 1815). Significant improvement was noted for the 3 knowledge variables: appropriate type of sunscreen to be used for outdoor play, highest UV Index number, and need for hats and shirts outside. Intentions to play in the shade increased from 73% to 78% (P < .001), with more modest changes in intentions to use sunscreen. Attitudes regarding healthiness of a tan also decreased significantly. Conclusions: Brief, standardized sun protection education can be efficiently interwoven into school health education and result in improvements in knowledge and positive intentions for sun protection.