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Nightmare Fuel: Wayside School
Wayside School. It's a children's book series by Louis Sachar, about a bizarre elementary school. For the most part, the stories are just silly and cute, but a few of them are definite Nightmare Fuel.
Spoilers below. And don't complain to Mr. Kidswatter if you peek.
Sideways Stories from Wayside School
In the first story of the first book, we're introduced to a teacher named Mrs. Gorf, who's able to turn children into apples, and does so over the most minor offenses. She ends up turning the entire class into apples; even the missing kids' parents have no idea what happened to them. The other school employees assume Mrs. Gorf must be a great teacher because of all those apples on her desk. Finally, the apples mount an attack, pin down the teacher, and demand to be changed back. At the end of the story, she accidentally turns herself into an apple via a mirror. Louis, the playground monitor comes in and, unaware of its true nature, eats it.
The story where a strange student shows up wearing layer upon layer of clothing, the clothing gets slowly removed only to reveal more underneath, a smell grows stronger, and the student grows nastier and meaner. In the end, the "student" is revealed to be a dead rat.
Wayside School is Falling Down
Allison accidentally ends up in Miss Zarves' class on the 19th floor. It is common knowledge among the students of Wayside that the building doesn't have a 19th floor, and that Miss Zarves doesn't exist. None of the students in the class have ever left the classroom, and they spend their time doing meaningless assignments, like memorizing the dictionary, and getting meaningless A's. Another student seriously wonders if they're in Hell.
It's even creepier when you think of Virginia and Nick and Bebe's brother, Ray. They're both a lot older than Allison (Virginia is old enough to be her mother!) and seem to think the nineteenth story is wonderful. The longer Allison spent there, the more she started to forget her previous life. That implies that Virginia and Nick and Ray have been there for years (decades in Virginia's case), have forgotten everything else and have been essentially held captive and brainwashed.
Mrs. Gorf returns twice during Wayside School is Falling Down.
Deedee finds Mrs. Gorf hanging upside-down in front of her on the monkey bars. When she tells her classmates and Louis, they decide to find out whether or not she imagined Mrs. Gorf reappearing by staying with her at the monkey bars. She doesn't return. However, Deedee happens to pass a large set of footprints after getting off of the monkey bars...
Later, Joe and John sculpt Mrs. Gorf's face out of potato salad. It suddenly comes to life, and threatens to turn the two of them into apples again. Fortunately, Joe and John gobble the potato salad up before she could do so.
Wayside School Gets a Little Stranger
Mrs. Gorf's son, Mr. Gorf, arrives. He wants revenge on the kids for taking his mommy away, and his power is his third nostril; it sucks voices up it and leaves the victims voiceless. The kids all lose their voices to him, all at once, except for Allison, who tries to alert Ms. Mush. Before Allison can tell her, Mr. Gorf takes her voice. But then Mr. Gorf slips up; he says "Have a nice day" using Kathy's voice, and Kathy is an anti-social jerk who would never be so polite. Realizing something is wrong, Ms. Mush saves the kids, since even she knows Kathy could never be so nice.
After Mr. Gorf stole the children's voices, he would call up their parents and tell them that he hated them while pretending to be the child.
One of the substitute teachers, Ms. Nogard, has a third ear that hears thoughts on top of her head. She managed to hide it under her hair until her ex-boyfriend discovered it. He couldn't deal with it and broke up with her. Since then, she uses it to be nasty to everyone, especially children.