A recent study illustrated the power of “nudges” in changing WASH behaviour. Robert Dreibelbis and his team tested the use of visual cues to modify behaviour. Here are pictures from two schools before the intervention, from their article in the International Journal of Environmental Research and Public Health. 
The baseline rate of handwashing was 4% of the students in the two schools.
The experiment involved ONLY adding paint to the walkway, handwashing station etc. Nothing else. Yet, within 6 weeks handwashing had blossomed to 74%!!
Known as “Nudge Theory”, this is related to the System 1 and System 2 thinking described by Danial Kahneman in his bestselling book: “Thinking Fast and Slow”
Food for thought!
Dreibelbis, R., Winch, P. J., Leontsini, E., Hulland, K. R., Ram, P. K., Unicomb, L., & Luby, S. P. (2013). The integrated behavioural model for water, sanitation, and hygiene: a systematic review of behavioural models and a framework for designing and evaluating behaviour change interventions in infrastructure-restricted settings. BMC public health, 13(1), 1.