This hilarious joke book is packed with laughs from start to finish. There are knock, knock jokes, Doctor, Doctor jokes, funny messages and much more. Joke-a-thon will amuse young readers for hours with over 250 funny jokes inside! This hilarious joke book is packed with laughs from start to finish. There are knock, knock jokes, Doctor, Doctor jokes, funny messages and much more. Joke-a-thon will amuse young readers for hours with over 250 funny jokes inside!