It’s not every day that Bookshelf speaks with an author who’s just come back from visiting her pediatrician, but 10-year-old Carrie Berk is not your typical writer. The New York City fifth-grader, along with her mother – Sheryl Berk, co-author of Soul Surfer and several celebrity biographies – writes the Cupcake Club series for Sourcebooks Jabberwocky. The third installment, Winner Bakes All, has just been published; four additional books are scheduled.

The series got its start as a two-page story that Carrie, then eight years old, wrote for fun while on a sleepover. She showed it to Berk, who in turn showed it to her agent, Katherine Latshaw of The Literary Group. While mother and daughter were on a cruise together, they received a call saying that the story had sparked interest from multiple publishers, including Sourcebooks, which was interested in developing it into a series.

Sourcebooks senior editor Leah Hultenschmidt, who usually works on YA and romance, inherited the middle-grade series after the acquiring editor (Rebecca Frazer, now with Orchard Books in London) left; Hultenschmidt edited the first book, and Sourcebooks Jabberwocky editorial manager Steve Geck, who joined the company in fall 2011, has worked on subsequent books. Hultenschmidt says she “thought it was fantastic” when she heard she’d be working with Carrie. “When I met her in person, she was so articulate and mature, but with a shy, quiet side that makes her seem like a real kid,” she says. “She knows exactly what her peers want to read, how they talk, what they talk about, and what interests them. She’s a focus group and author all in one.”

A peek at some marked-up manuscript pages for the first book in the series, Peace, Love, and Cupcakes, shows just how serious the now-fifth-grader is. A mention of a winter dance prompted the query: “A winter dance in fourth grade? That usually happens in high school.” In a few spots, Carrie disputes the amount of time that passes in the book – two months would be better shortened to one month, or even two days, she suggested.

“My favorite part of the writing process is probably editing,” Carrie says. “My mom writes the first draft and prints it out for me, and then one day during the weekend I take a pen and I mark through her whole draft. When I’m done with all my edits, we sit on my bed, we go through it, and sometimes we disagree. But my mom usually takes my edits because I know more about kids.”

Berk is happy to let her daughter’s expertise shine. “It’s her voice. She’s not kidding when she edits these pages. When she reads it, she’ll go, nope, that does not sound like how a fourth or fifth grader would talk, or nope, that is not the way my teacher would say something, or the pacing here is just a little too fast. I feel like I’m being graded by a fifth grader! But I think it resonates with kids because it truly is a child’s voice.” The recipes are another draw; they’re developed by Jessi Walter of Taste Buds, a children’s cooking school formerly known, appropriately enough, as Cupcake Kids. The Berks offer their enthusiastic input on each recipe pre-publication.

Examples of Carrie's marked-up manuscript pages. Click on each for a larger version.

Although Sheryl Berk herself is an author, she says that Carrie’s impetus to write came from other sources. “In second grade she was writing all these Judy Moody stories because it used to be one of her favorites. She met Megan McDonald; we went to a book signing, and Megan told her, just keep writing. And she took that as: I’m going to keep writing Judy Moody. Her teacher, Ms. Schottland, said to her, ‘You know what, Carrie – you should write some more original stuff. Don’t use everybody else’s characters; come up with your own.’ That’s how she came up with this idea.” Ms. Schottland’s reward? Immortality: she’s one of many real-life people in Carrie’s life who appear in some form or other in the books.

With at least another four books on the way, Carrie’s got plenty on her cake plate; she’s also the new owner of a Havanese puppy (look for an appearance by said pup in book four) and when she’s not in school or at ballet class, she’s tending to her cupcake-review Web site and Facebook page, which has more than 23,000 “likes” (and counting). And next year, the Cupcake Club explores a new medium – the stage – when New York City’s Vital Theatre Company develops the first book in the series into a musical. The musical versions of Pinkalicious and Fancy Nancy both got their start at Vital, so it’s no wonder the Berks are sweet on the idea.