The rules are the same whether you’re at a beach or chilling by the hotel pool – you should supervise your children in the water at all times. For young children, that means going in the water with them and keeping them at arm’s length; for older kids, it means a poolside adult needs to be keeping an eye on them (without chatting, texting, or reading).
A smart move before your beach vacation is to learn infant and child CPR – classes are available online from the American Red Cross.