We check crowd levels too, but I agree that AK might be a good place to start. Last trip, we made the mistake of putting AK toward the end of the vacation, and DS6 and DD4 weren't as impressed as they would have been if we had done it closer to the beginning. They normally love zoos and animal parks too, but I think after all the excitement and stimulation, they couldn't just relax and enjoy AK. They did love the Lion King show though.