This is with kids so your mileage may vary, but I will sometimes say in a joking way, "So, which of those topics adults always ask do you want to discuss, favorite sport, what you want to do when you grow up," maybe list 1-2 more. The joking manner tends to be good to break the ice with new kids in my department, anyway.
So, maybe adopt a lighthearted tone and ask, "So, what aspexct of the holiday season do you wish to discuss?"
Other tiems I'll ask if they did anything interesting,a nd if the kid says "no" (not uncommon) I'll ask, "Did you do anything boring?" in a lighthearted tone and then (or without the "boring" question I'll ask, "Did you do anything..." and throw in a really uninque adjective. (Unique, thought-provoking, etc.) Again, kids may enjoy the lighthearted and unique approach better than adults but I find they seem to enjoy me. But, maybe it's becasue I've learned to be myself and they accept me for that becasue they're just learning how to interact themselves.