well, not necessarily free, it's just included in the price of the cruise, but it's soooo much fun!! i think they've changed it now to where the teen hangout is in the smokestack, but when i went it was in a coffee shop and, i'm being dead serious when i say this, parents were only allowed in w/ the teens on the first night. after that, they were banned from entrance!
i hardly saw my family at all during the 3 days we were on the ship. the only time i was in the same room w/ them was at night when we were sleeping or at dinner because i was told i had to go. It's so unbelievably fun and there's so much to do that you never get bored.