The Tarpon Springs Sponge Docks are a fun place to spend a day.
The half-mile road is filled with souvenir shops, Greek food places and the aquarium and it is located on the water with all the sponge boats.
May sound strange, but I recently recommended it to a client and he went with his wife and young son expecting to only spend about an hour and was there for half a day because they were having so much fun.
Check out this site for more info.