A Bad Case of the Sillies is the first part of the nineteenth chapter of Wayside School is Falling Down.
Plot
Allison wonders if maybe her homeroom is in fact on the 29th story since there’s no 19th. After getting knocked down the stairs a short way by Ron and Deedee and her jacket torn, Allison proceeds to class and finds everybody ignoring her, especially when Jason accidentally swallows his pet goldfish. A frustrated Allison leaves the room and finds herself inducted into the classroom of Miss Zarves.