When the kids get bored, the first activity that comes to my mind is usually cleaning objects with a toothbrush. Ok, that's a total lie. It's usually going outside to play followed by putting on a video if I'm feeling particularly lazy. Luckily, they don't get "bored" too often yet. I don't know why the kids love washing things with a toothbrush so much, but they do. It involves water, soapsuds, a small tool and accomplishing a relatively easy task.
Here's the Sadester washing seashells that we collected from the river. This particular river is totally nasty, so the seashells really needed to be cleaned and probably should have been bleached too:Washing rocks in the pool:Eli's carwash, er' tonguewash: