Frozen kidsicles

With the dipping temps we have had ( below zero here last night) How do you try to make sure your kids stay warm? When you are around them of course you can make sure they are bundled up but what about when they are at school or a friends house? Do you give them warnings that without those gloves and hat ( however uncool they may think it is) they can get frostbite and loose a finger? Growing up in Alaska my mom told me to watch my pierced ears in the winter and to keep my ears covered or the metal of the earrings would freeze and I could lose my ear lobe !( I don’t know if this is true). So do you tell them to stay warm and hope for the best?