The other day I hear this from the back seat:
Zoe: Mom, can we look for good and bad numbers?
Me: (confused) What are good and bad numbers?
Zoe: You know! Good and bad numbers. Like we learned in school. Come on, you remember.
Me: (racking my brain. Sometimes this takes a while) OH! Do you mean odd and even numbers?
Zoe: YES! Can we look for odd and even numbers?