Junie B. Jones and all of Room 9 are getting ready to graduate from kindergarten! Their teacher--known to our heroine as "Mrs."--distributes their fresh white caps and gowns ("Cats and gowns, cats and gowns!" Junie hollers), and makes her students promise to keep them in their boxes until the big day. But Junie B., being Junie B., is sure that just one peek on the way home won't soil her gown. And then she must show off to her stuffed animals with a lot of whirling and skipping, which of course makes her thirsty. But guess what? "Grape juice can go wrong."