Tell them not to fret over it though. My DH would ask me each night what he needed to wear-shirt & tie or polo shirt and khackis. As soon as dinner was over he'd automatically go back to the cabin and change back into shorts and a t-shirt. They will have plenty of time to change after dinner and won't miss any of the activities. If you send your kids to dinner with the club, they can wear shorts and t-shirts then.