Hello Barry,
You will find lots to do on St. John. Your posts asks many questions. First I would recommend a book about StJ. I found "Off the Beaten Path" by Gerald Singer very helpful. You can find it by clicking a link above or use this link to order it from VI Traders.
http://www.vitraders.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=21-54&Category_Code=gub
It will give you ideas about what you may wan to visit on while on the island. As far as your other questions;
- I have not visited durning Carnival so I can't help you there.
- I would recommend two snorkeling beaches on StJ for a family with kids, each depends on the weather or my mood, Cinnamon and Little Lamsur. Each of these will provide good snorkeling and barring windy conditions are excellent beaches for a family to visit. Cinnamon is on the North Shore and Little Lamsur is on the south shore. If it is windy at one, the other is likely to have mild conditions.
- I like Starfish Market because they have the selection and hours I like and are convenient to Fish Bay, which is my preferred area to stay in.
- I would recommend renting a car. I use L&L rental.
www.bookajeep.com
- As far as excursions for a 6 year old. I imagine that an island full of beaches, lizzards and jungles full of lizzards and ruins would be enough to keep him or her busy.
- I sometimes ship food with us but the additional cost per luggage item has changed that for me. The $15 cost of a checked bag is most of what I save by shipping. Of course I travel with only my wife and I and sometimes with another couple.

Hi! I'm sure once you get to the Westin, they will be very helpful in suggesting places to go with your 6 year old and also good places to snorkel, but here is some info for you:

As for Carnival, we've never been there for that either, but the link below is from this very site and has good info on Carnival to give you a good idea what it's all about:

www.vinow.com/general_usvi/carnival

As for snorkeling, there are many beaches to snorkel at, but don't turn away from Trunk Bay either. There is wonderful snorkeling there and they have the fun snorkel trail where you can read about different things you are seeing. You may have gone there last year, but it's good to go when cruise ships aren't in port in STT so it's not as crowded. I also second what Toes In the Sand suggested about Cinnamon Bay and Little Lameshur. Maho Bay in the morning is also good for snorkeling if you want to see turtles in the sea grass, but other than that, not much else to see there, as far as snorkeling. Another good suggestion for snorkeling is Leinster Bay/Waterlemon Cay, although not sure if you would be able to do this with your 6 year old, but here is the site for info: www.stjohnbeachguide.com/Beaches/leinster.html This was probably some of the best snorkeling we have done. You park your car and then walk on a trail to get to where the snorkeling is. We saw tons and tons of starfish, tons of tropical fish, octopus...it was amazing. If you are able to do this, make sure you bring lots of water with you because it will be hot while you do the walk. Some of the trail is shaded, but after walking in the heat, and then snorkeling, you'll want to hydrate. Oh, and the walk was about 1/2 hour, if I remember correctly, but SO worth it.

In case you didn't make it to Hawksnest Beach, that is also a great, calm beach to hang out on. We didn't snorkel there, but your little one will enjoy playing in the calm water.

Again, check with the Activities Desk at the Westin, they will be a big help to you.

Hope you and your family have a blast on STJ! 🙂