We had such a get time on vacation in the Florida Keys. I have been going there since I was eight. This time, we flew, but we have also driven there in the past. My parents always drive.
The water is crystal clear. We did not see any whales, but we saw dolphins, manatees, and a wide variety of fish while snorkling just off of our beach.
We always stay in the upper keys just south of Islamorada on Lower Matecumbe Key mile marker 75.5 on the bayside. There is less wind on the bayside.
We have been staying at the following place since I was 17. This is a very kid/family friendly place.
http://www.keysdirectory.com/topsider/index.html
Dolphin Research Center is a great place to visit on Grassy Key. www.dolphins.org
Hope you have a wonderful time where ever you end up going.
Gretchen