When my boys were young I always took them for a day trip to Naples Beach.
I don't know the name of the beach but it is a BIG public beach with a nice boardwalk built by the city. It is jut past Tampa on the Gulf.
I love the Gulf water much more than the Ocean, cleaner and less high waves.
And the best thing about the Naples beach is the Shark's teeth. They don't know why, but petrified sharks teeth wash ashore at this beach more than any other FL beach. You can walk along the water line at low tide and pick up sharks teeth everywhere. They are black and shiny, look like black rocks until you pick them up and see they are teeth. Just like the ones you can buy at the tourist stores for $5 and up.
One year we found so many that I went into each of my boys classrooms and we did a craft together. I bought some thin copper wire and some leather that loked like shoelaces but on a long roll. I had the kids wrap the copper around the tooth and they each got enough leather to either make a neclace or keychain. The class loved it and my boys were so pleased.
There are tons of places to eat along the main road of Naples and if you ask at the gas station in town someone will give you directions. I know the way to go, but don't pay attention to street names etc... You would get lost with my way. Peggie