If you prefer to play it by ear rather than take a "formal" shore excursion, the kids might enjoy a horse & carriage tour of Nassau. That is within walking distance of the ship.
I have heard that there are beach toys you can check out at Castaway Cay for the little ones, and you can also rent a bike with a child seat. You may also want to rent floats or buy some cheap floats to bring with you.
Barb
Visit the Platinum Castaway Club at: www.castawayclub.com
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