I've come to the conclusion that you can take a group of teenagers, give them a place to hang out for awhile, sling some food at them, and provide a few simple things to do, and they will be happy.
Today we had about 20 juniors and seniors from school over--just invited any who wanted to come after school was out at noon. It was an interesting mixture of kids, not at all a typical group who hangs out together at school. I asked with trepidation if any of them wanted to paint ornaments, figuring they would think it was "uncool" to do so. The girls immediately said yes, and after awhile even some of the boys decided to paint ornaments too! Meanwhile, some of the others played Scattergories and then Guesstures while an older movie played in the background, and after awhile went out and shot baskets. They grazed on chips and rice krispie bars, with a little fudge thrown in after awhile. They came and went all afternoon, for about five hours.
And they all seemed to have a great time.