OBJECTIVES: To characterize handwashing behaviors of children and assess the efficacy of a waiting room-based hand hygiene intervention at improving handwashing ability. DESIGN: Prospective randomized pilot study. SETTING: Emergency department waiting room at a freestanding urban pediatric hospital. PARTICIPANTS: Children (8-18 years) and their parent. INTERVENTION: Participants were randomized to glow gel hand washing without hand hygiene education or glow gel hand washing with hand hygiene education. After participants washed with glow gel, "dirty areas" were illuminated using a black light, and hands were scored. A questionnaire about handwashing behavior was administered. All subjects returned 2-4 weeks after intervention to repeat glow gel hand washing and the questionnaire. RESULTS: Sixty pediatric patients and 57 parents were recruited, with 77% of patients returning for follow up. Patients were 50% male, 58% Latino, 28% African American, and 8% Caucasian. At the initial visit, 91% of children reported hand washing after using the bathroom and 78% reported hand washing before dinner. On the basis of objective scoring, all children improved handwashing ability when compared with the initial visit (P = .02) and were more likely to use warm water at follow up (P = .01). Parents did not significantly improve in handwashing ability (P = .73). CONCLUSION: Glow gel hand washing is an effective method to improve children's handwashing ability. This short-term intervention was effective even in the absence of specific hand hygiene education. This intervention could serve as a valuable public health measure to teach hand washing in healthcare settings.