Arcadia Public Library

The monstrous Turbo Toilet 2000 is determined to take revenge on George, Harold, and Captain Underpants.

After the principal of P.S. 88 is turned into a frog by a bumbling magician, the frog bargains for the chance to act as principal until Mr. Bundy returns from his "family emergency."

"Friends and pranking partners Miles and Niles face a tough challenge when their favorite goat and nemesis, Principal Barkin, is replaced by his stern, no-nonsense father, Principal Barkin Senior, who turns the school into boot camp"--

When Mr. Lincoln, "the coolest principal in the whole world," discovers that Eugene, the school bully, knows a lot about birds, he uses this interest to help Eugene overcome his intolerance.

When Harold and George turn fourth-grade teacher Ms. Ribble into the evil Wedgie Woman, she gives the wedgie of doom to unsuspecting people who stand in her way--including principal-turned-superhero Captain Underpants.

When she is named Principal for the Day, Frannie wonders if principals assign their own punishment when they get in trouble for using office supplies or accidentally set off the fire alarm.

Frustrating his sister with his tendency to transform into a monkey whenever he gets hyper, Clyde is given an extra-firm reason to try to control his energetic behavior when a new school principal moves into the neighborhood.

George, Harold, Captain Underpants, and Sulu the bionic hamster battle the three ridiculous Robo-Boogers in an attempt to turn the Bionic Booger Boy back into Melvin Sneedly.

Orville and Wilber Riot rescue a damsel in distress, are mad scientists, and defeat a bully through Operation Armpit.

Living in the boiler room of the school where her father is janitor seems normal to fourth grader Martha Snapdragon, until she has experiences with an evil principal, the class bully, and a mysterious giant spoon, all reminiscent of the Arthurian legends.