Easter Crack-Ups: Knock-Knock Jokes Funny-Side UpAn excellent Easter basket stuffer! Enjoy over two dozen knock knock jokes that will crack up the whole family. Knock, knock! Who's there Heidi. Heidi who Heidi eggs under the bushes! Lift the flap to reveal new punchlines and surprises. A day at the park becomes even more exciting with all the fun Easter activities. Search for eggs, race with them, and paint them.