For ages 8+ years. Anybody, anyplace, and anything becomes a punch line for knock-knock jokes: Knock-Knock! Who's there? Heidi. Heidi who? Heidi Claire, something smells delicious. Try it with Daniella. (Daniella so loud, I can hear you just fine.) Or, with disguise. (Disguise killing me with these knock-knock jokes.) Soon you'll turn everybody and everything into your own knock-knocks, and you won't be able to stop till somebody knocks you down!