Jeff Kinney's latest Diary of a Wimpy Kid, "The Ugly Truth," is on sale nowThough his signature character Greg Heffley is known to millions of middle school readers as the wimpiest kid in comics, cartoonist Jeff Kinney must be feeling pretty strong about his books these days. "The Ugly Truth," the fifth and latest volume in the Amulet "Diary of A Wimpy Kid" series, debuted as the #1-selling book in the country, besting even President George W. Bush's memoirs in its first week. Beyond that, Greg Heffley makes his debut this weekend as a stories-tall balloon in the Macy's Thanksgiving Day Parade and a second film adaptation of the "Wimpy Kid" series is on tap for March 25 of next year. So how does the most successful children's cartoonist in America celebrate his vast success? With a cross-country tour in a purple bus emblazoned with pictures of his characters, of course.

"We're on this giant purple bus that sleeps twelve -I think the Beach Boys had it before us!" Kinney told CBR News shortly after the release of "The Ugly Truth." "We're traveling across the South and trying to get out to fans that we don't ordinarily visit. We're doing big stage shows that fit about 2,000 people. It's cool! What I have done a lot more of has been going out to Hollywood during the movie to be a part of the filming process. What I've done a lot less of is visiting schools and going to conferences, but right now we're on a fully-loaded tour where I'm on a bus with the two actors who play Rowly and Greg in the film."

Touring to and meeting with the legions of young "Wimpy Kid" fans has given Kinney a fresh perspective on what works best in the series, which combines comics illustration with traditional prose. The cartoonist explained that while his books have gained acclaim for their portrayal of Greg as a kid whose attempts at fitting in in the tough world of Middle School are undermined at every turn by his own hubris, his own job involves balancing that deeper character work with plenty of funny drawings. "I try to make the books as high-minded as possible. I think that's just to serve me and make it feel like I'm not just writing gags," he said. "I don't know if the kids pick up on it or if they're terribly interested in the over-arching thematic stuff. But the fourth book was about memories -the re-shaping of memories by the person who's doing the recording - and the fifth book is the heaviest book yet. It was really my attempt to answer the question of whether or not Greg would get older.

"I've realized for some time that there's a cap to the number of stories I could write because eventually the kids are going to run out of ground. They'll get older. Then I really wondered if I'd created literary characters or cartoon characters. Because if they're cartoon characters, they don't grow up. The book 'The Ugly Truth' is about puberty and growing up and leaving childhood behind or not. By the end of it, I feel like I've settled the issue, and I feel very satisfied artistically, but I'm not sure kids will pick up on the message."

Greg Heffley takes to the air in this year's Macy's Thanksgiving Day ParadeKinney added that while many of his young fans may not dig into the broader metaphorical work he considers while writing the books, they certainly see the self-defeating nature of Greg's actions in dealing with school, parents and siblings. "I think that kids can understand his mentality. I think kids are smarter than we think, and they understand that Greg's behavior is not to be emulated or imitated. What they like is that the story doesn't feel like there's an adult in it who's moralizing to them. I think a lot of the things that Greg does are very relatable, anyway. To me as an adult, they're relatable since I'm writing with an adult's point of view for a child character, but I think there are a lot of kids in literature that act like adults. Part of the appeal to Greg is that he acts like a kid, and that's why the voice seems authentic."

In "The Ugly Truth," Kinney mixes a number of well known rights of passage with Greg's somewhat selfish world view to play up the humor his audience expects. "The lock-in is a good example," he said of a sequence in the book where Greg and his buddy Rowley stay overnight at school and navigate dealing with girls and sleeping in a gym. "From a narrative perspective, it's almost unimportant. You could remove the whole section, and the book would hold together just fine. But it is the longest section because I was having fun with it. I had a lot of ideas for jokes and situations I thought were funny. It's a good example of me writing not to impress the critics but to give the kids as many gags as possible. At the end of the day, kids aren't reading my books for the stories. They're reading them for the gags. And if I have a narrative thread that's good enough, that's just fine. But what I'm going for is getting one or two laughs on every page."

And the power of the characters has spread even wider since "Diary of A Wimpy Kid" made its way to the silver screen earlier this year. After the film's strong performance both in terms of sales and reviews, plans to continue the story on screen were never in doubt, although this time Kinney has had a greater opportunity to work with the filmmakers hand-in-hand. "I was probably on the set for 25 out of the 45 days this time around. I helped out with the script and wrote a bunch of stuff for the marketing that's going to be used on the DVD that's straight out of the book that we filmed," he said. "And I've really gotten to know these kids well. I consider them to be family. I'm sitting here right now with [actors] Zack [Gordon's] mom and Robert [Capron's] dad. We've had so many fun times together that I feel very close to them. As far as the performance goes, I don't talk to them about that. It's not my role. It's the director's role. I also don't talk to them about that because they seem to know the characters very well. Each of these kids have about 85% of their DNA in the characters already, so it's not difficult to get a good performance out of them."

Ultimately, Kinney's focus remains on his books where his designs on keeping the characters consistent and relatable are benefiting from lessons learned from another cartoonist whose work appealed to both kids and adults in a different way. "There are two worlds we're dealing with here: one is the movie world where the real life kids playing the characters are getting older. Then there's the comic book world where the kids don't need to get older if I don't let them," he said. "It's like how Charlie Brown has a first day of school every year, but he never gets older. In the book world, I've made the decision to keep the kids the same age, because I'm not expecting that the kids who read these would want to follow the characters into high school. And quite frankly, I'm not interested in writing about high school issues. We've never even said how old Greg is in the books, and I think readers will suspend their disbelief and believe that these characters go on and on."

The WImpy Kid busPart and parcel of making that reality work for his readership is Kinney's control of his cartooning, which in the story is the art of Greg, whose Diary is often expressed and explained with comic stories and anecdotes. "I made the decision very early on to keep the character look fairly consistent. Something close to what we were talking about with suspension of disbelief before, I found that if you were looking at 'Peanuts' comics that looked like they were from an earlier incarnation as opposed to ones from later on, the ones from earlier became obsolete in your mind. I've seen that with many comics that have evolved over time -'Bloom County' or even 'The Simpsons' animated show. When you see the old ones, you're kind of turned off because you feel that's just when they were finding their legs. For me, I took a whole year to just keep drawing and re-drawing the characters so that they didn't look different from book-to-book. There are some subtle changes in my art style which are accidental, but the characters generally look the same."

Overall, the one way in which the "Wimpy Kid" series doesn't gain influence from more traditional comics narratives is the fact that Kinney himself rarely interacts with the larger comics community - an effect the cartoonist finds more than a little bewildering. "It has really been the strangest thing. I haven't gotten any real interest from the comics community, and I don't really feel like I'm a legitimate part of the comics community because of the nature of my cartoons being in book form," he said, even though the series was originally pitched and sold at New York Comic Con. "I harbor no ill will, but I've also said and I continue to feel like - I'm about to go speak at the National Cartoonist's Society, and I know I couldn't break into that business. There are people there who are very interested in hearing what I have to say, but I'm also very excited and honored because it's a world I could never get into."

Whether Kinney and his work are picked up by more of the traditional comics community remains to be seen, but for now his fans don't seem to care what the "Wimpy Kid" books are classified as so long as they keep coming out.

"The Ugly Truth" - the fifth volume in Kinney's "Diary of A Wimpy Kid" series -is on sale everywhere now. For more on the series, check out www.WimpyKid.com