This presentation by Megan Williams, Senior Manager, Behaviour Change, describes how the NGO Splash uses schools as catalysts to promote city-wide community water, sanitation and hygiene (WASH) coverage. There are examples of research on school and household nudges in Addis, Ababa, Ethiopia; clean water kiosks for schools in Kathmandu, Nepal and city-wide training in 1,500 schools on hygiene and behaviour change in Kolkata, India. The presentation was given during the Webinar: “Systems approaches to hygiene behavior change – lessons across WASH, health, and education” hosted by the Global Handwashing Partnership and IRC.