"Junie B. Jones and Her Big Fat Mouth" by Barbara Park

Meet the World’s Funniest Kindergartner—Junie B. Jones! Junie B.’s having a rough week. First she got punishment for shooting off her mouth in kindergarten. And now she’s in big trouble again! ’Cause Monday is Job Day, and Junie B. told her class that she’s got the bestest job of all. Only, what the heck is it?