The riddles are clever. On each page, you are supposed to count a certain item within an illustration. The riddles give hints as to how to count them the easiest way. Each page has it's own problem. A clear answer key/diagram is in the back of the book. Some knowledge of multiplication is necessary. But a child just beginning to multiply could see the benefits of learning their times tables so that they could solve the riddles in the Grapes of Math.