A crash course in changing the world.
I would organize a themed painting event "water in our lives": each place in different countries has a super long canvas, kids and adults will all be invited to paint on it. They can draw anything about water, either realistically or using their fantasy: how water is used in their daily life, where does water come from and how is water cycled, what spectaculars things can be done with water, what would life be like when water is in shortage and what doohickeys may help saving water... Then the canvas will be switched to different countries and exhibited on the main streets. People who have sufficient water supply will get to know what life with inadequate water would be like and thus raise awareness of saving water. People with insufficient water supply can express their wishes and draw attention to their circ***tance. Great ideas of saving water can also be spread.