Most young children have watched Scooby-Doo on television so he is a familiar character.  So having books based on the same character and teaching math concepts is a great idea–they are learning without even knowing it.  Oddzilla is a monster created by a man who programs it to steal one object in a pair.  He then advertises that if you are missing one of something, he’ll have one to sell you to make a pair.  This book is short and sweet, great sewn binding, and teaches all in one.