A.J. and his friends get a Personal Digital Assistant named Miss Porter as a substitute teacher, who can order pizza and tell endless jokes, but grows power-hungry when her system is changed and tries to take over Ella Mentary School.

When Mr. Granite falls ill, A.J. and the gang endure a wacky week with a perpetually cheerful substitute teacher who wears a clown costume, uses hand puppets to talk, and uses magic tricks to saw students in half and make them disappear.

There is an elegant substitute teacher in class today, but Katie's attempts to impress her keep going wrong.

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

In a series of letters a student laments the absence of her teacher and daily routine, but she soon realizes there are benefits to mixing things up, and that perhaps having a substitue teacher is not so bad after all.

When Milton Worthy learns his classroom's pet ferret is the evil mastermind behind a dastardly plot for world domination, it's more than just about any kid could handle. But then not every kid is the son of a member of the super-secret, super-awesome Society of Substitutes! Now it's up to Milton and his substitute teacher mom to save Beacher Elementary School before time runs out.

When sixth-grade classroom terror Jacob Wonderbar and his friends Sarah and Dexter find a spaceship crashed in the woods near their suburban neighborhood, their discovery leads them to a series of adventures including space travel, substitute teachers, kidnapping, and more.

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.