My latest mission is to teach my kids to turn off the back yard tap when they've gotten the water they need. When they're out back they're constantly using it - to water their gardens, fill the dog dish, or just for play.
My son is particularly bad for leaving the tap running. It's as if he likes the sound in the background while he plays. Sometimes I think it's out of convenience, because maybe turning the stiff tap is hard for little hands. In any case, he showed a preference for leaving it running, until I started reminding him to turn it off.
Last night while I was brushing his teeth, he started turning off the tap between rinses. Wow! Not only is he remembering, he's teaching me a lesson too, because I hadn't even realized I was leaving it running.
Oops... good thing someone's paying attention ;-)