You don’t have to get into the curvature of space-time, but you can tell your kids that Santa uses deep scientific knowledge to see a different map of the universe, one that contains roads most people don’t know about. The Jolly Old Elf may have found a way to jump or drop from one house to the next without having to travel along the same line you’d use. If they’re still asking questions after that, pull up Time Bandits on Netflix streaming. If that doesn’t satisfy, you might have a future physicist. –How to Scientifically Explain Santa Claus to Your Children.
I have always cited sources: “Well, in ‘Twas the Night Before Christmas, Santa is referred to as an elf… but in The Year Without A Santa Claus, there are elves helping Santa… Which do YOU think is the more reliable source?”