Katie Kazoo, Switcheroo

The class 3A trip to the Natural History Museum is turning out to be a disaster:  Many of Katie''s excited classmates are acting up, and they turn on Katie and call her a goodie-goodie when she won''t join in!  Even worse, their tour guide, Mr.  Weir, is a big meanie!  Still, when Katie turns into Mr. Weir and causes a big disaster of her own, it''s up to her to make things right-and save Mr. Weir''s job!