We chose this excursion on a recent Alaska cruise. It was a bit muddy, but good fun for all ages--we were a group of 5, aged 7-44. One kart broke down but the guide gave his up and the show went on. Great scenery despite a bit of rain. Would highly recommend for families with school age kids and teens as well.
A side note: we were on Celebrity Infinity and when we received our tickets in our stateroom it stated drivers must be 21 with valid license despite what it says on Celebs own website and their current on board brochure. Found excursion desk unhelpful in this matter, so I called Adventure Karts directly and they confirmed it is 16 with valid license.