Have you ever gone diving with one of the dive companies in Aruba?
Paul and I have gone out with a few different dive companies and enjoyed ourselves lots.
Have you ever considered taking SCUBA lessons?
A resort SCUBA course would give folks a good idea if this is something they would be interested in.
A resort course gives a few hours of pool training and then a shallow 1 hour (less than 30') ocean dive under the watchful eyes of dive masters.