If you want to wait until you arrive there will be multiple vendors holding signs offering an excursion to the Turtle Farm, often coupling that with a stop at Hell.
Any tour to the Turtle Farm will be happy to drop you off at a beach location on the way back to the port. It would then be up to you to take a taxi or catch a bus to get back to the tender pier.
Several popular beach locations in Cayman have good and easy access for food. Royal Palms, SeaGrape, Seven Mile Beach Public Beach and Tiki Beach are some of the more popular locations due to available services. For just a few hours with small kids I'd go to Seven Mile Beach Public Beach and eat from the food trucks or next door at Calico Jacks. The kids will enjoy the beach and the playground equipment.
^Thanks!
Anyone know what the cost of a taxi ride is supposed to be to 7-mile (or back)?
And how much the Turtle Farm Tour is when you buy from a vendor?
(These vendors are from TF? How do you trust them?)