Junie B. Jones is a Graduation Girl by Barbara Park

It's kindergarten graduation!All the children in Room Nine are excited when they get their bright white graduation gowns. Mrs. says to keep them in their boxes until the big day. But Junie B. Jones just can't help herself. Then—uh-oh!—an accident happens! Can Junie B. find a way to fix things? Or will graduation be a spotty dotty disaster?