The fourth book in this successful series delivers 300 new laugh-out-loud knock-knocks, question-and-answer jokes, tongue twisters, and more National Geographic Kids Just Joking 4 is packed with 300 more of the silly jokes that kids love, paired with photos of laughing animals and funny people. Featuring National Geographic Kids' signature square trim size and candy-colored palette, this hilarious party-starter is perfect for tossing into a backpack to share with friends at school or camp.