Hi Skip. I used to go to Fort Lauderdale 3-4 times a year from 1978 to 1987 to visit my grandparents. I know it's been 18 years since I've last been there, so things have probably changed some, but this is what I found.
Lauderdale is a major metropolitan area with many things to do. Your usual activities of many movies, malls, resturants, as well as some amusement parks are there. There is also Golf, Tennis, lots of pools, and such.
One thing that should be taken into account in Lauderdale in the summer is the weather. It is usually unbearably hot and humid and very rainy, with temps between 85 and 90, and very high humidity every day. Additionally, if you are planning any outdoor activities, keep an eye to the sky, because seemingly every afternoon between around 3 and 6pm, there are showers and thunderstorms with heavy rain, lightning, and some hail. Any outdoor activities in the summer would best be planned before noon as that is the part of the day that is less hot, and less likely for rain.
Have a good trip. As I said, it's been a while, so you probably need to talk to someone who has been there more recently than me to get specific activities which are there now. I just wanted to give you a brief overview of how it generally was when I was there.
Mitch