There was a terrible mistake. Wayside School was supposed to have been built with thirty classrooms all next to each other in a row. Instead it was built with the thirty classrooms all on top of each other- thirty stories high!

That may be why all kinds of strange stuff happens at Wayside School. Especially on the thirteenth floor. It is a school full of unusual characters too. Mrs Gorf, the meanest teacher in the world, Terrible Todd, who always gets sent home early and John, who can only read upside down.