Captain Underpants books are quickly becoming a kids' must-have.

His eight Captain children's books have more than 25 million copies in print in the USA. Pilkey also has created The Dumb Bunnies, Big Dog and LittleDog, and Ricky Ricotta series, the latter with artist Martin Ontiveros.

Others include Dogzilla, Kat Kong and Caldecott Honor book The Paperboy.

Not bad for someone diagnosed as a child with learning and reading problems, behavior problems and severe hyperactivity. "I remember one teacher who used to rip up my books and tell me I'd better start taking life more seriously, because I couldn't spend the rest of my days making silly books," he notes on his Web site, www.pilkey.com.

"Fortunately, I wasn't a very good listener."

Call Pilkey, 37, the savior of the "reluctant reader," children who resist books. But few kids can resist booger jokes and bathroom humor. In a sea of moralizing tales for the peewee set, Captain Underpants springs forward, battling Talking Toilets, Professor Poopypants, Wicked Wedgie Woman and Deputy Doo-Doo. After writing eight CaptainUnderpants books, Pilkey foresees about a half-dozen more.

In an unusual move, Pilkey's next two epic novels in the series are being released in two volumes: Captain Underpants and The Big, Bad Battle of the Bionic Booger Boy. The first part, The Night of the Nasty Nostril Nuggets, hits stores Tuesday. The Revenge of the Ridiculous Robo-Boogers goes on sale Sept. 30.

Each has an announced first printing of 1 million copies.

"He's a genius" at getting reluctant readers into "the reading habit," says Brooklyn, N.Y., public librarian Barbara Genco, former president of the American Library Association's Association for Library Service to Children. "Pilkey has never lost touch with what preadolescent boys (7 through 9) find funny."

Genco recognizes that some parents find the bathroom humor offensive, but "his books are just superb," she says. Genco praises their humor and pacing. Moreover, she notes that his books resonate deeply with "a lot of kids who don't feel successful at school." Like all great comic writers, Pilkey mixes pain and humor, Genco says.

It is not just "reluctant readers" who love Pilkey's books. Ryan Hallahan, 6, who's entering first grade, has been reading them for a year. The Ridgefield, Conn., resident says, "I think they are funny."

Pilkey's first-grade year was not a happy time. Growing up in Cleveland, he was such a disruptive class clown that his teacher put his desk in the hall. There, he would draw and later write stories.

"I think most of my teachers expected me to be a failure," Pilkey says via e-mail, which is the communication mode he uses for interviews. "It's probably a good thing that I had so much to rebel against." He dislikes labeling children with terms like hyperactivity. "I really can't answer for anybody but myself. It made me feel stupid ... like I was destined for failure."

After struggling through elementary and high school Pilkey credits his parents with being supportive. Today, "they are proud of his success, although they're kind of embarrassed about all the potty humor (they're very conservative)."

His feelings about educators changed in college. While Pilkey was a freshman majoring in art at Kent State University in Ohio, an English teacher complimented his creative writing. In a cartoon retelling of his life on his Web site, Pilkey depicts himself being carted away in an ambulance, in severe shock, after hearing actual encouragement from a teacher. He won a contest for writing and illustrating the children's book World War Won in 1986. He has been writing and drawing ever since.

Self-promotion has little to do with Pilkey's success. He dislikes public speaking and is going on his first book tour in five or six years. He lives in Oregon.

Ostensibly, the Captain Underpants series is written and illustrated by Pilkey's protagonists, George Beard, 9½, and Harold Hutchins, 10. The two pals are fourth-graders at Jerome Horwitz Elementary School in Piqua, Ohio. They suffer under the lash of the evil Mr. Krupp, the principal, and teachers with names like Ms. Ribble. But one day, the boys, who are funny, smart and have ADHD, discover they can hypnotize Mr. Krupp into believing he is a superhero, Captain Underpants. Off go Krupp's clothes except for his white jockeys. On goes his cape, and suddenly he is flying through the air yodeling "Tra La Laaa" and fighting for truth, justice "and all that is preshrunk and cottony."

Who is Mr. Krupp? Says Pilkey, "He's a composite of several cruel and unusual teachers and/or principals I endured over the years."

Pilkey taps into feelings of rage, hostility and despair that school can create in pint-sized underachievers. In The Adventures of Super Diaper Baby, Pilkey wrote "Don't Forget to boycott standardized testing!" Why? "It's impossible to measure a child's intelligence, competence or ability through a series of multiple-choice trivia questions.

"I try to get the point across that not everybody thinks the same way. There are obvious benefits to being 'book smart,' but I think common sense and creativity is just as good (maybe even better)."

It is no coincidence that the academically gifted Melvin Sneedly dutifully obeys the sign created by Harold and George, "Please Wash Your Hands in the Toilet," in the "sixth epic."

For children having a hard time in school, Pilkey notes, "Try to remember that being unsuccessful in school doesn't automatically mean you'll be unsuccessful in life. Lots of people who didn't excel in school still went on to have successful lives. For example, Thomas Edison's teachers thought he was retarded ... but he ended up doing pretty well for himself."

Sally Shaywitz, Yale University professor of pediatrics and author of the critically praised Overcoming Dyslexia: A New and Complete Science-Based Program for Reading Problems at Any Level, notes that Pilkey's "own experiences as a dyslexic child growing up no doubt gave him sensitivity to the imperfections in all of us."

In her book, she urges that parents point out to their children that Pilkey, among many other achievers, struggled to learn to read. "Dyslexic children can imagine and dream and grow up to be wonderful authors like Dav Pilkey," she observes. "The ability to write and imagine has little to do with being dyslexic."

One of the most unusual aspects of Pilkey's books is his periodic use of phonetic spelling in the comics that George and Harold create. (They write words like "pore" for "pour.") Pilkey says he deliberately uses this kind of writing to encourage his readers to try writing and drawing themselves. "I'm hoping that kids will read George and Harold's comics, notice the mistakes and realize that creativity doesn't depend on proper spelling, flawless grammar or even perfect artwork. I'm hoping these 'less than perfect' comics will encourage kids to try being creative on their own, without the often paralyzing fear of 'messing up.' "

Before you dismiss Pilkey as simply a purveyor of juvenile bathroom humor, a children's book he wrote and illustrated, The Paperboy, was named a Caldecott Honor book, the children's literature equivalent of being an Academy Award nominee. Pilkey admits he could have a more trophy-studded career, "but who wants to be taken seriously?" On the cover of The Dumb Bunnies, there is a sticker declaring the book to be "too dumb" to win an award.

His girlfriend's books are prize winners. Cynthia Rylant won the 1993 Newbery Medal for her children's novel, Missing May. They met at a writers' group, he says, and "we've been dating for the last 15 years. I think she's beginning to like me."

The two share a passion for dogs. Pilkey calls Little Dog, the abused and abandoned puppy he adopted, his "best pal."

Although Pilkey is very open about himself and his history on his Web site, he treasures his privacy. But he's not the J.D. Salinger of juvenile literature. For one thing, he's very funny. Asked if he is reluctant to become the poster boy for ADHD achievers, he responds, "I really don't want to be a poster boy. I wouldn't mind being on their calendar, though." The reason? "Because I could dress up like a snowman. I hope I get December."

As to the question, do you like kids more than adults, Pilkey responds: "Of course. Who doesn't?"