Kids really want to go on a beach vacation. Original plans fell through, so am now open to ideas. Time frame is early August. Open to anywhere from Ocean City, MD to the Caymans. I would prefer blue water, white sand and incredible snorkeling.
The Keys are nice but they don't have many natural beaches. If you pay for a nicer resort, they make a small beach. The water will be nice and the snorkeling will be awesome. The John Pennekamp Coral Reef State Park is some of the best shallow diving around. Really easy to snorkel, with most of reefs between 10' to 30'. Miami isn't very family friendly and tends to be expensive but you have access to great beaches and great reefs.
The Bahamas offer good beaches and snorkeling as well. Never been impressed with the food there so I prefer to rent somewhere that I can cook my own if I go. I've never been there but my friends have said great things about Bimini.
If I was going today, I'd be going to Cozumel. Its a small island but its a short boat ride from Playa del Carmen which if you know how to find them, has some great restaurants at affordable prices. The snorkeling is good but a bit deeper at 30' plus. You also have the Cenotes Mayas which can be easily snorkeled. Not a lot in the way of fish but they are beautiful all the same.
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You are picking a time during hurricane season which is iffy for some areas. We just came back from Aruba which has all the preferences on your list. The hotels are all incredible. There are all inclusive hotels that are great. Aruba is not in the hurricane belt and has beautiful sandy beaches, snorkeling and fabulous hotels. It is called one happy island we found out while we were there because you can stay at one location and you are welcome to swim in the pools and visit all the hotels on the beach. We took a great walk along the entire beach from the divi all the way to the last hotels on the beach, stopping to drink, eat and swim all along the way. We were only had four days but they were fabulous.
During non hurricane season or if it is not a problem for you to travel during that time - if you have not been to the Atlantis Paradise Island with the family - it is an absolute MUST. Everything in one place you don't even need to leave other than the fabulous snorkeling excursions.
Good luck in your search for a family getaway.
Greetings from Ocean City, MD! Okay, Pro's = Ocean City in August is family friendly. Amusement parks, jet ski rentals, fishing, Assateague Island for camping and of course, the beach. Con's = Blue water is dark blue not island blue. White sand? Not here. Snorkeling you can do on your own but OC does not have any snorkeling that I know of. Hope this helps out. Enjoy!