Silver Dollar city 3 years ago. Easily the worst theme park in America, and completely boring to children and teens. Right next to Dolly Parton's stampede, which is not only rigged, but they haven't changed it at all in ten years.

Others I have been to:

disneyworld: omg so much fun
disneyland: not quite as much fun as disney world
six flags over texas: nice, not great.