Megan McDonald is the author of over 60 books for children and young adults, including the Judy Moody and Stink series, which celebrate their 20th anniversary this year. Her books are a worldwide phenomenon with over 32 million copies in print in 28 languages.

McDonald will discuss her creative process and new book, “Judy Moody, Book Quiz Whiz,” at the Portland Public Library as part of the Peaks Island Illustration Institute series Saturday.

Q. What were your favorite books as a child?
A. I lived in a house full of books with four sisters who were all readers. We read the entire Nancy Drew series — all 56. Also the Little House on the Prairie books (by Laura Ingalls Wilder), Grimm’s Fairy Tales and of course (Beverly Cleary’s) “Ramona,” who’s kind of a precursor to Judy.

My particular favorite growing up was “Harriet the Spy.” I loved that Harriet was always sneaking around and spying on her neighbors — and she wrote it all down. She was spunky and fearless, and always had creative ideas. She was such a great strong-girl character.

Q. When did you start writing?

A. My family tells me that when I was in the third grade, I started to stutter. We all told stories at our big dinner table, but with four older sisters I could never get a word in edgewise. So my mom went to the bookstore to get help. Instead of a book on stuttering, (the bookstore) gave her “Harriet the Spy.” It came with a little spiral notebook and (my mom) told me I should use that to write down everything I wanted to say.

That was the beginning. Then in the fifth grade I had a teacher who recognized that I loved to write stories, and every month he would save a corner of the mimeographed school newspaper for me. It was a really great thing my teacher did, because it was not a school assignment but writing for fun, to create. My first published story was called “The Plea of the Pencil Sharpener.”  I share this with kids because they always ask, “Why would you write about a pencil sharpener?” and it’s a good way to demonstrate that anything can become a story.

Q. How did your own childhood influence the writing of the Judy and Stink books?
A. I had so many sisters (one of whom is Portland Press Herald photo chief Michele McDonald) that when I started hatching the idea of the first book, I wanted to write about them, to use the funny antics, the real-life stories. Like the fake hand in the toilet from the first book, that was a real joke that I played on my sister. And the Toad Pee Club was a real club. But rather than give Judy sisters, I changed it to be a younger brother, Stink, because that meant as a writer I got to step into the role of the bossy big sister.

Megan McDonald when she was 3 years old, refusing to get up off the neighbor’s driveway in Pittsburgh. Her sister, Michele McDonald, now photo editor of the Portland Press Herald, took this photo with her Brownie camera. Michele McDonald/Staff photographer

Q. Where did Judy herself come from?
A. A lot of it is similar to me. I was and am a moody person. Kids would ask me, “Are you ever in a bad mood?” and “Can you write books when you’re in a bad mood?” I realized that around the third grade, kids are starting to be aware of moods. I thought it would be fun to explore moods. You could show so many sides of a character that way. And I wanted kids not to be afraid of being in a bad mood. But Judy has so many other qualities — she’s exuberant and funny and passionate — I didn’t want it to just be a kid in a bad mood. It’s important that we see her as someone with flaws and disappointments like we all have.

Q. How do you explain the success of Judy?
A. Judy is an Everykid. She’s someone every kid knows, someone who’s magnetic and you want to be around her because something’s always going to happen. She’s such a real character to them that many kids tell me they want to meet her or be her best friend or sit next to her. And humor is a big part of it. Funny books cut across everything — race, class, age. In letters from kids, those are the two major themes: the books are so funny and they feel they can relate to Judy.

Q. Do you have a goal as an author? Do you just want to amuse kids? Or do you feel a responsibility to help them understand themselves or navigate the world?

A. For me it’s more about understanding themselves. But I don’t start with a lofty idea or anything heavy-handed. Then you’re just trying to promote a message rather than tell a great story and create a character. With characters we feel strongly about, we see ourselves and learn through them. Kids can learn through Judy’s successes and setbacks how to navigate the world. For example, I wrote a book where she tells a lie and starts to itch all over, and she has to resolve that. But I didn’t start out trying to teach kids about lying. I don’t begin with a message but I end up there somehow.

Q. How did you develop Judy’s unique vocabulary — words like roar and rare? You seem to enjoy playing with language.

A. I do love playing with language, with sounds of words and puns. When I was that age, my sisters and I had secret languages. We made up words and had names for everything from the car to the pillow on the couch. Silly things — like if you said the word Harvey you got mercilessly tickled. But I wanted the Moody books to feel timeless, and rather than using contemporary expressions I made up things for Judy to say. When she was in a bad mood she would say “ROAR!” For a joyful mood I didn’t want to use awesome because that could get dated, so I looked up awesome in the thesaurus and it had rare. So that’s what Judy says. And now all these parents and teachers ask me how I had my finger on the pulse of an 8-year-old and knew that this is what they were saying – but they’re only saying it because they read Judy Moody.

Q. Your latest book is really a celebration of some of your favorite books, including Astrid Lindgren’s “Pippi Longstocking.” Why does Pippi play such an important part in that story?

A. Pippi is right up there with “Harriet the Spy” in my youth. Again, it’s that sort of rule-breaking and turning things upside down. I always have Judy with her feet on the pillow and her head off the end of the bed, like Pippi. My sisters and I, we read our books that way once we had read “Pippi Longstocking.” She has the Judy Moody uniqueness, and Judy would embrace that. And so Book Quiz Whiz’s final showdown comes down to that last question about Pippi’s full name. That was a great way to end it.

Q. Judy’s bucket list includes getting to the fourth grade. After 20 years, will she ever make it?

A. Poor Judy. I think Ramona was in the third grade for 25 years. I don’t have plans to age Judy. I just love this age so much — that was my favorite age and my favorite year in school. I find third-graders so smart and funny, not jaded. And Judy’s kind of a handful — I can’t think about her as a teenager.

Q. Has your audience changed since you started writing her? Are you seeing any of this “kids getting older younger” phenomenon?

A. It’s really true. When the first book came out, my audience was fourth- and fifth-graders, even though Judy’s a third-grader. Now fifth-graders are feeling this is too easy. I’ve got first- and second-graders reading them. It’s been a real shift. I don’t know if they’re learning to read sooner or are being urged to move more quickly into chapter books. I hope not. Picture books are so wonderful, I would hate for any kid to miss that.

Q. What would 28-year-old Judy look like? Would she be a climate-change activist?
A: I think she would. She’d be an inventor or a scientist or an activist.

Q. Fourth grade is on Judy’s bucket list. What’s on yours?

A. I long to go back and do picture books again — they are really my first love. And I’d love to do a graphic novel. I’m not an artist but just doing the text would be fun, and trying to think more visually. I’d love to write all the speech bubbles.

Q. What’s next for Judy and the gang?
A: In the next Judy Moody, Judy has the Monday blues. She gets the idea to make every day into a wacky holiday — National Pencil Day — and exhausts herself trying to celebrate them all.

Amy MacDonald is a children’s book author and freelance writer. She lives in Falmouth and can be reached at AmyM781@gmail.com.