Mrs. Jewels
Mrs. Jewels teaches in the classroom at the very top of the thirty-story Wayside School. She took over the class after their original teacher turned into an apple and was accidentally eaten. The story begins with Mrs. Jewls attempting to teach the class the concept of the size of a million. This leads to a recurring subplot about the class trying to collect one million nail clippings.
The nail clippings idea characterizes the teaching methodology of Mrs. Jewls. She is beloved by her class in part because she is inventive and creative in her teaching process. The teacher becomes a center of mystery partway through the story, however, when students discover she has a mystery closet.
The book opens with Mrs. Jewls writing on the blackboard about the Ultimate Test. Throughout the book, the story returns to this subject. Mrs. Jewls assigns a spelling bee, a Jump Rope Arithmetic, and the Stairway Quiz as part of this test. She must deal with the nail clipping collecting, the Ultimate Test, and protecting her secret closet while also dealing with the arrival of the Cloud of Doom.
Mrs. Surlaw
Mrs. Surlaw occupies the seventh floor of the Sideways school. She is the school's librarian. Her idiosyncratic personality is initially characterized by the presence of a stuffed walrus on her desk that is so large it is actually bigger than some of the students.
Mrs. Surlaw is also introduced as being one of those librarians obsessed with rules of behavior. She institutes a series of cautionary regulations which must be followed. She will not allow students to eat, drink, yell, or do somersaults in the library, In addition, students are only allowed to hug her walrus after they have already checked out a book.
The ultimate characterization of Mrs. Surlaw, however, may be how the students of Mrs. Jewls respond to both adults. They generally tend to love and respect their teacher. On the other hand, the students in Mrs. Jewls' class universally are scared of the tough librarian.
Mr. K and Dr. P
The chapter which bears the title "Mr. K and Dr. P" opens with an Author's Note informing readers that the names of the characters have been omitted in order to protect confidentiality and avoid humiliation. In fact, the names of the two title characters are not difficult to figure out: Mr. Kidswatter and Dr. Pickell.
When Mr. Kidswatter arrives at Dr. Pickell's office, he is wearing a bag over his head. The Cloud of Doom has strange effects on the school, including the aftermath of a playful staring contest between Mr. Kidswatter and a student named Dana. The consequence of losing the contest is that Mr. Kidswatter's face remains stuck in a less-than-attractive pose.
He has come to the doctor to get his face unstuck. This is a situation that presents Dr. Pickell with quite a challenge. When he takes the bag off his head, the principal reveals a face in which his tongue is sticking out, one cheek is puffed out, and one eye is tightly shut while the other eyebrow is comically raised. The doctor settles on a unique style of hypnosis involving a well-timed pie in the face.
Louis
Louis is the groundskeeper of the playground at the school. Mr. Kidswatter is jealous that the kids seem to like the groundskeeper better than the principal. Louis advises him to do nice things for the kids as he does himself.
Louis has many adventures in which he interacts with the students. He overinflates a ball so that it explodes. This event occurs when the Cloud of Doom casts a shadow over the playground.
In one of the chapters, Louis and Mr. Kidswatter have a conversation in which it is revealed that Louis has made money writing books about Wayside School. Mr. Wayside asks him to include a chapter about himself. It is strongly intimated that the books Louis has written are the Wayside series and that this is the book in which he fulfills the principal's wish to be included.
