We did the Atlantis Sub on St. Thomas this past June with an 8 year old girl and two boys ages 6 and 10. The kids LOVED it. We got to see so many fish, it was amazing. Some adults seemed to get claustraphopic (it's a little tight in the sub) but the kids did awesome. Also, since the Sub trip doesn't take all day we also went up the inclide on St. Thomas. The view is beautiful and they have a snack shop/bar and shops at the top. We also had time to shop in town.