A crash course in changing the world.
I would have the event at a beach, and there would be a cornered off area for inflatable toys and kayaks. The event would be free, but little shops, cafes and markets would sit on the perimeter of the beach for people to enjoy. Volunteers would walk around asking if people would like to dontate.
When night comes, music would play loudly for everyone to dance to, and shows and dances would be performed on a stage.