Koreshan State Park is interesting, the historic settlement.
Kayaking from just about anywhere is fun, as long as it’s not overly windy.
Sanibal Thriller, or something similar, for dolphin fun.
Check out downtown Fort Myers for its shops and eateries.
Lakes Park with kids is fun … the water area, train, and/or get a surrey bike and ride the easy trails
And if going to Sun Harvest for ice cream … the key lime-chocolate twist is the only flavor to get. Or if it’s ice cream you want … Love Boat
Take a boat cruise to Key West