Where can we store our luggage after a cruise from Ft Lauderdale when we get off of the ship? Any ideas?

The cruise port is only about 15 minutes from the airport; they are on opposite sides of I-95. So find a cheap hotel room near the airport and store your luggage there until you are ready to go to the airport. You may even find one that has a free shuttle. There are a bunch of hotels near by like Hampton Inn, Motel 6, Best Western and Holiday Inn. You would have to reserve for the last night of your cruise and tell them you will not get there until the day the cruise ends and that you want a late checkout. Put everyone's bags in there and go. Then before its time for the airport everyone has a place to freshen up ( with 8 people you may want two rooms).

Depending on your flight time, and what time of year or day of week you do need to factor in that the airport will be crowded and security can be slow.

Depending on you flight time, a possible solution is to take a cruise line excursion at the end of the cruise which takes you and your luggage on a tour in the area and ends at the airport.

There is not really anywhere to store luggage and once you get to FLL, nothing in walking distance anyway so might as well just stay there.