In this article, you'll find a list of the best books with similar reading levels that are always funny, sometimes gross, and checked out time and time again by the hundreds of Captain Underpants fans who come to my library. This combination of riotous elements has kept children entertained (while reading, of all things) for a generation.But what if your little guy or gal has torn through the whole Captain Underpants series, from the original Adventures of Captain Underpants all the way to Captain Underpants and the Preposterous Plight of the Purple Potty People? How do you keep them reading?You find them another series they like just as much.