If you're trying to do something different with teens, hunting ghost towns is a great time. Getting outside, exploring, hiking, and even learning how to use GPS and maybe some geocaching, if you're into that sort of thing.
We have been looking around Unionville, Nevada, but there are lots of resources to finding ghost towns all across America. Bodie, California, is the king daddy, and they are easier to find in the West, but they are everywhere. Just search "ghost towns near [your town]" and you should find what you're looking for.
Have you been hunting ghost town hunting? Where did you go?