Hi! We did SNUBA in St. Thomas when we went on the
Disney cruise in 2001. It was EXCELLENT! Our DS was 10 years old then and was able to come with us for the adventure.
We had to arrange for the excursion ourselves, as it wasn't a Disney excursion then (don't know if it is now or not). We just found them on the Internet at a friend's suggestion (
www.visnuba.com) and booked for a time in the middle of the day. We took a taxi to and from Coral World, where they're located and had no problem with being rushed by the ship's itinerary.
They only take a maximum of 6 people per guide (two people per raft), and I liked that from a safety standpoint as well as the fact that the small group allowed us to get to know the people we were diving with a little better, which always makes things more fun. The excursion begins with a short introduction to SNUBA and safety along with a practise session in waist-deep water. I thought that was very well done and made for a more enjoyable dive.
One thing I liked particularly at St. Thomas (as opposed to SNUBA in Key West, for instance) was the fact that we dove off a protected beach instead of taking a boat out to sea. This was much easier for beginners, because you start in shallow water without much wave action and the ocean floor just slopes away gently - this makes it not so frightening as having to jump off a boat into deep water and being buffetted by waves. The calm water also made it easier physically, which was important when diving with a skinny little 10-year-old.
The only draw-back of diving off the beach was that, as we approached the swimming area on the way back, the occasional swimmer would try to get a free ride on the raft carrying the tanks. This made pulling the tanks a little harder, but the dive masters did attempt to discourage the hitch-hikers.
The area where we dove had piles of lovely corals and interesting marine life (again, better than our Key West experience where we saw lots of cool rays, but that was about it - just water and sand). The water visibility was very good! As with all SNUBA, you can only dive to about 20 feet (that's how long the hose to your air supply is). I'd estimate the deepest part of the area we dove was around 30 to 40 feet. They made a point, though, of telling the group that there's no pressure to dive any deeper than you're comfortable - that was also important when diving with a first-timer.
We used this experience to determine whether or not our DS was interested in becoming certified for SCUBA and it was a great success. Altogether, we'd recommend it highly.
Hope that helped. If you have any specific questions, just let us know.
Cheers,
Pirate