I personally would ask the teenagers where they would like to vacation. If you prefer, pick 4 or 5 spots you'd be pleased with and let them choose from the list.

Nothing worse than disinterested/unhappy teens on vacation, so you might as well make it fun for them.

And all you folks who keep recommending Maine...you DO know what's going to happen, don't you? Some things are better left as "best kept secrets', no?