We did this excursion in March and we liked it. The best part for us was diving off the side of the boat - I have posted a great pic of my husband in mid-air over that gorgeous blue water. The pirates really spent a lot of time with the kids and younger teens - I think your 13 year-old will really like it. The only problem was that the excursion started at 7:30 am!
Carnival Fascination Oct 2008
Carnival Freedom March 2008
RC Mariner of the Seas Feb 2007