When George and Harold hypnotize their principal into thinking that he is the superhero Captain Underpants, he leads them to the lair of the nefarious Dr. Diaper, where they must defeat his evil robot henchmen.

Tired of following the strict rules of their grumpy replacement principal, second-grader A.J. and his classmates try to find a way to bring back eccentric but lovable Principal Klutz, who was fired for bringing a wild turkey to the school's Thanksgiving Day assembly.

Harold and George's time-traveling Purple Potty lands them in an alternate universe where everything seems delightful, but evil lurks just beneath the surface, and leads to a battle between Captain Underpants and his own evil twin.

When the teachers of Ella Mentry School go on strike, A. J. and the gang meet a new principal who does not believe in rules and says that the students do not have to learn anything if they do not want to.

Hubie is running for president against Doris. But he doesn't think he stands a chance against the free ice cream that she's giving away to voters. Plus, to stay in the race he has to do crazy stuff like shaking Coach Kong's paw and Mrs. Green's claw, and kissing a bunch of babies. Hubie's chances look slim. Will being the candidate who stands for something---not just who stands on top of something--be enough to win him the race in the end? --from...

Mr. Bundy, a school principal, discovers that he should be careful what he wishes for when a grateful elf grants him three wishes.

"Big bad Mr. Bundy? Mr. Bundy is the principal at PS 88. And it may be hard to believe, but he once came nose-to-nose with the big bad wolf, who gobbled him up in one bite! 'Gulp!' One thing all the kids at PS 88 know for sure is that their favorite principal is never far from zany (mis)adventures"--Back cover.

After the principal of P.S. 88 gets caught up in a messy spell by one of his students, the other kids rally to help him out.

"Molly gets things stuck in her head sometimes. When she sees a jar of candy on Principal Shelton's desk, she absolutely needs to know how many candies are in that jar! Luckily, her two best friends, Simon and Rosie, are ready to help her find the answer--even if it means detention for all of them!"-- Provided by publisher.

"Meet Mr Bundy! He's the principal at PS 88, and believe it or not, he was once magically turned into a slimy green frog. He played leapfrog, ate bugs, and even croaked, "Ribbit!". One thing all the kids at PS 88 know for sure is that their favorite principal is never far from zany (mis)adventures."--Back cover.