E.T.
We were just in Florida in early April. We took a day away from Disney and went to the Kennedy Space Center. It was great! Seeing the space shuttle Atlantis was probably the highlight for me. The bus tour of the launch pads got a little long, but it was interesting to be that close to the launch pads and to see the Apollo display that is out by the launch pads. You can pay a little more to eat lunch with an astronaut. We didn't do it this time, but definitely want to do it next time. They also have some 3-D IMAX movies. We saw one about the space station that was really good.
When my brother lived in Florida we went to Homosassa Springs State Wildlife Park. It is a small park that you can probably see all of in about half a day. All of the animals are native to Florida, except for a hippo that was purchased from I think a circus that went under. My favorite part was the manatees. You can get pretty close to them.
My kids liked eating at Joe's Crab Shack.