My kids invariably leave the lids off their markers. So we end up with tons of dry markers sitting around. I used to gather them up and throw them away.
But no longer!
Lately, the favorite game is taking dry markers to the bathroom sink. They fill the sink with water and float the markers. Pretty soon, little rivulets of color are snaking through the water, making beautiful patterns.
Because our bathroom sink is white, the only color in the water comes from the markers. They've learned more about mixing to make new colors than they ever did with paint. And the mess goes down the drain when they're done.
We noticed that if you float a marker long enough, the tip turns white. But if you leave it out to "dry" for a while, the color usually returns--and the marker is no longer dry. It is once again useful for coloring on paper (provided you still have the lid somewhere).
So now I keep a container full of dry markers by the bathroom sink so the kids can play whenever they want. No more wasted markers.