* George and Harold's revenge on the teachers and Melvin by becoming "Principals for a Day" at the end of ''Attack of the Talking Toilets''.
* The TakeThat comics they draw making fun of Melvin in ''Big Bad Battle of the Bionic Booger Boy'' and ''The Revenge of the Ridiculous Robo-Boogers''.
* In ''Wrath of the Wicked Wedgie Woman'', the boys trick Mr. Krupp into giving Ms. Ribble a card that says "You're one hot mama! Will you marry me?" Also doubles as a CrowningMomentOfFunny.
** Also,when Captain Underpants defeats Robo George and Harold 3000.
* As revealed in his biographical blurb, Dav Pilkey's principal as a child told him he'd never make a living as an artist and that he should stop wasting time "drawing silly comic books." Fast forward to now...
-->''Fortunately, Dav was not a very good listener.''
* ''Captain Underpants and the Sensational Saga of Sir Stinks-A-Lot'' [[spoiler: showing Harold as a happily-married gay man with three children in the future,]] is seen as one of the most progressive moments in the whole series. Even better is that it was presented in a matter-of-fact way, without making a big deal out of it.
** While this inevitably drew ire from conservative groups, as well as fans who saw that this was completely unnecessary, some of his now-adult or teenaged fans who read his books in childhood, many of whom turned out to be LGBT themselves, have practically ''exploded'' with support and happiness. Also a CrowningMomentOfHeartwarming, seeing how much it means to many LGBT teens to see an LGBT character in a children's series they loved so much.
* George and Harold creating quite possibly their greatest comic ever to inspire the cavemen in ''Return of Tippy Tinkletrousers''.