It’s been two decades since Amelia penned and illustrated her very first journal, Amelia’s Notebook, in which she recounts – in a lively spray of words and pictures – the travails of adjusting to life in a new town and school. Written by Marissa Moss (“except for words and pictures by Amelia”) and published by Tricycle Press, that paper-over-board book spawned a series that follows the feisty girl through elementary and middle school. The series celebrates its 20th anniversary – as well as Amelia’s middle-school commencement – on April 20, when Creston Books issues Amelia’s final oeuvre, Amelia’s Middle-School Graduation Yearbook.

A chance purchase that Moss made while shopping for school supplies with her son led to Amelia’s creation. Moss spotted and spontaneously bought an old school-style composition book, which brought her back to her own elementary school days. “I had to buy it for myself, because it immediately reminded me of the notebook I had as a kid,” she said. “I sat down and wrote what I remembered about being nine, and that eventually became Amelia’s Notebook. I still have that first draft!”

That book and its sequels have quite a peripatetic publishing history. After several New York City publishers rejected Amelia’s Notebook, the San Francisco-area author placed the book with the local Tricycle Press, then the children’s imprint of Ten Speed Press. “The bigger houses turned down the handwritten notebook format as ‘too odd,’ ” Moss recalled. “It was not a picture book, nor a middle-grade novel, and publishers worried that librarians and booksellers wouldn’t know how to handle such a strange hybrid. Long before Diary of a Wimpy Kid, Dork Diaries, and the graphic novel explosion, only a small press like Tricycle was willing to take a risk on such an innovative format.”

That gamble paid off when the book earned rave reviews, and Tricycle Press released three follow-up notebooks. After an excerpt from Moss’s original Amelia book ran in American Girl magazine and garnered a deluge of mail from young readers, American Girl bought Tricycle Press’s four-book Amelia’s Notebooks backlist, and released 11 new titles in the series before Mattel acquired the company. Moss’s Amelia backlist was then sold again, this time to Simon & Schuster’s Paula Wiseman Books, which published 16 additional notebooks chronicling the heroine’s middle-school years.

With sales totaling more than five million copies and translations in six languages, Moss’s series returns to its small press roots on its 20th anniversary. The author, who founded Creston Books in 2012, believes that her series’s circuitous publishing path has landed its finale in the right spot. “It’s only fitting that Amelia ends up back where she started, at a small quirky press,” she said.

Moss credits the ongoing popularity of Amelia’s notebooks to the books’ playful storytelling style meshing words and pictures, which – the author knows from frequent feedback – has inspired many teachers to use the series to encourage their own students to write. And Amelia’s comedic voice has also helped the series withstand the test of time. “Nothing extraordinary or amazing happens to Amelia,” Moss says. “It’s her point of view and her humor that speak to kids and strike a universal chord, given the international interest in the series.”

Moss will herself encourage readers to take a stab at notebook-style storytelling on May 15, when she stops by Politics & Prose in Washington, D.C., one of a handful of bookstores she’ll visit to promote Amelia’s Middle-School Graduation Yearbook. There, she’ll teach a journal-writing class for aspiring middle-grade diarists, which Kerri Poore, the store’s events coordinator for children and teens, reported is quickly filling up.

“Parents, teachers, and kids themselves like the idea of being able to express ideas through both words and pictures,” she said. “The illustrated journal format of the Amelia Notebooks series, which was a real precursor to a genre that is now commonplace, definitely appeals to readers. And the author really understands kids – and that comes out in her books. I’m sorry to see the Amelia series end, but Marissa Moss is an excellent writer, and it’s always great to see what else she has in the works.”

As Amelia leaves her middle-school years behind, Moss said she too must move on – though somewhat reluctantly. “I just don’t think I can bring Amelia to high school,” she mused. “It’s sad, because she is a real part of me. But at the same time, I’ve been handwriting these notebooks for 20 years, and that hasn’t gotten any easier with time. I draw everything, including the notebook lines and the splotches on the covers, so my hand is very tired!”

Amelia’s Middle-School Graduation Yearbook by Marissa Moss. Creston Books (dist. by PGW), $12.95 Apr. ISBN 978-1-939547-09-5