A.J. and his friends think that Ms. Todd is the strangest substitute teacher in the world, and they decide to investigate her.

An elementary school class must contend with a substitute teacher that seems like the monster Frankenstein.

After she eats his homework, Zack suspects that his substitute teacher Mrs. Wolfowitz is a werewolf and uncovers her bizarre secret.

"Keep your friends close and your enemies closer! When Snowball, the puffball hamster in Ms. Kim's classroom, accidentally sips the teacher's leftover protein shake, she transforms into a monster like Beacher Elementary School has never known before. It's all hands on deck to stop Snowball before it's too late. And to do that, Milton Worthy is going to do have to team up with Noah, the part-time classroom ferret, full-time evil mastermind! Will Milton...

"Oh, no! Noah, the classroom's evil pet ferret, has stolen everyone's lunch--and worse yet, he's done it on a day when Milton's mom, the class's go-to super-sub, is off on another assignment. Will Milton be able to foil Noah's most fiendish plot yet or will they lose their lunches for good in the gooiest, stickiest, biggest food fight ever?"--

Sam, Lucy, and Antonio have a new substitute teacher, who happens to be the great-great-grandson of Orson Eerie, the evil scientist whose spirit possesses and infects their elementary school--and the friends are afraid he may be trying to bring Orson back to life.

Sixth-grader Jake Ali Mathews is slowly settling in at his new school and has a new best friend, Michael, but a substitute teacher arrives who instructs by having her students help with a fledgling pet-grooming company, which strains his friendship and tests his growing popularity.