I would definitely recommend the high rise area. We have had 18yo guests with us before and they love that area and so do I. Many many options for night life, clubs, casinos and bars. Don't know how renting a timeshare from an owner works with the age restrictions, but that might be a way to get around the 18yo thing. Folks your age would probably enjoy the Surf Club as there are many activities at the resort. The low rise/Eagle Beach area is more quiet and laid back and might not provide the graduation party/celebration atmosphere you are searching for.