Carlina Teteris / Getty

N. K. Jemisin, the only author to win the prestigious Hugo Award for best science-fiction or fantasy novel three years in a row, partly credits fan fiction for her ability to draw in readers.

Jemisin started writing fan fiction, in which authors imagine new stories based on preexisting fictional works, while in grad school for counseling. “I was miserable and lonely. I didn’t have a lot of friends, or stress relief,” she told me. “Around then was when I became internetted, and one of the first communities I discovered was a fan-fic community.” Through talking  with other authors and writing her own stories about Dragon Ball Z (among other things), she found friends, got feedback, and, as she put it, “blew the cobwebs off writing abilities I hadn’t used since college.”

For instance, this writing helped her hone her ability to hold readers’ interest. “Fan fiction tends to have a built-in hook because it’s written in a world you’re a fan of; you’re predisposed to like it,” she said. “You have to find a way to make it not just the world that people are tuning in to read, so they are interested in your story.” To this day, Jemisin said, she still writes fan fiction, and treats it as a way to try out new genres and skills, such as using the second person, which she does in the Broken Earth trilogy, which earned her the three Hugos.

It’s common for contributors to fan-fiction websites to see their skills develop like this. In these online communities, writers of all ages and skill levels—from adolescents still refining their grammar to professional adult authors such as Jemisin—are learning and teaching others how to write, and write well.

A fan-fiction site is a uniquely energetic learning environment. Unlike in the classroom, where a writing prompt is as likely to be met with groans as with enthusiasm, writers on fan-fiction websites are thrilled to be there, excited to write, and passionate about the material—because it’s based on a book, TV show, movie, video game, or something else they already love. “It’s really clear that if you have a genuine interest and a personal identification with the topic that you’re learning about, your learning is going to be more engaging and, as a result, more successful,” says Katie Davis, a professor at the University of Washington’s Information School and a co-founder of its Digital Youth Lab.

Davis, along with her University of Washington colleague Cecilia Aragon, recently spent nine months studying a couple of fan-fiction websites, focusing mostly on young authors writing on fanfiction.net. (Older, more experienced fan-fiction authors tend to prefer the website Archive of Our Own.) They published their observations in a new book called Writers in the Secret Garden, and described their theory that people on these websites are actually teaching one another to write through a kind of sprawling, communal learning that Aragon and Davis call “distributed mentorship.”

Though writers may develop traditional two-person mentor/mentee relationships on fan-fiction websites, the researchers posit that much more often, people are being diffusely mentored by the entire community. An author frequently receives many small pieces of feedback in the form of reviews (sometimes thousands on one story) that are in conversation with one another and that “are cumulatively much greater than the sum of their parts,” Aragon told me.

One example from their book is how commenters responded to a writer’s question about portraying Princess Luna, a villain from the show My Little Pony: Friendship Is Magic. One person wrote: “From the limited amount of stories that I have read, Luna is usually portrayed as a gamer or somewhat out of touch with modern culture.” Then another offered their take on that advice: “While I’m picky about the kind of technology that I would introduce into a story, Luna being behind the times is right on the money.”

These communities also “allow for a lot of different forms of expertise,” says Rebecca Black, an informatics professor at the University of California at Irvine who has studied fan fiction (but who wasn’t involved in Davis and Aragon’s project). “Even if you aren’t the best writer, you might know everything there is to know about a certain character in the series.” People can switch between the roles of teacher and student, depending on their strengths and weaknesses.

Generally, fan-fiction writers’ strengths are effusively celebrated, and any feedback on their weaknesses is very gently conveyed. Reviews of fan fiction are overwhelmingly positive—Aragon and Davis found that out of a sample of 4,500 reviews on fanfiction.net, only 1 percent were what they called “non-constructive negative” reviews, or “flames” (such as: “I never thought that human spawn could create such a horrible piece of crap”).

Tamsyn Muir, a science-fiction writer from New Zealand and the author of the new novel Gideon the Ninth, remembers the reviews on her early fan-fiction stories (parodies of Animorphs and long, gritty tales based on the Final Fantasy video games) as almost entirely positive. “You didn’t have to do that well to get a lot of positive feedback,” she told me. In fact, in her early days of writing and posting fan fiction online, she said, she got only one actual critique. “Somebody had said, ‘I think this story is okay, but it feels a bit template. It just feels like a very generic story.’ I was so angry, because it was the first piece of really constructive criticism.” The anonymous review turned out to be from her brother—after he watched her fume all day, he fessed up. “He was like, ‘I don’t want you getting complacent,’” Muir said.

While it probably takes more than unalloyed positivity to strengthen one’s writing, hearing what readers respond well to is useful for writers, and an outpouring of encouragement may well motivate writers to keep writing, which can only improve their skills. “People often discount the positive feedback, but for a lot of struggling writers and English learners, those copious amounts of positive feedback were really important,” says Black, who has studied how fan fiction helps English learners grow as writers in their new language.

Still, constructive criticism (or “concrit”) is a welcome and integral part of fan-fiction websites (although some writers or communities may specify that they’re not looking for concrit). When fan-fiction reviewers offer a specific critique, they often present it in the middle of a “compliment sandwich,” according to Muir and Black, slipping negative feedback between the bread of effusive praise, and often adding a self-deprecating comment such as “But what do I know?” to soften the blow.

Aragon and Davis’s research also found that the communal tutoring happening on fan-fiction websites leads to a quantifiable improvement in people’s writing, at least by one metric. They analyzed 61.5 billion words of fan-fiction stories and 6 billion words of reviews from fanfiction.net, tracking the “lexical diversity,” or complexity of vocabulary, of users over time. They discovered that for every 650 reviews writers received, their vocabulary improved as much as if they had aged one year. (The average age of authors in this sample was just under 17, so this may not hold true for older writers—even if they are honing other, more advanced, less measurable skills, such as story structure, pacing, or character development.)

Jemisin said she’s found several trusted readers to share her work with through writing fan fiction, and compared it to the sort of peer workshopping that happens in college creative-writing classes. “Fan-fic is one big giant writing workshop,” she said, “one that’s voluntarily joined and cranks on and on.” Fan fiction, then, is a way to instantly get extensive amounts of targeted feedback in a low-stakes environment where, unlike at school, no one’s being graded.

It also teaches something that schools rarely do: what it’s like to write for a real audience “versus a teacher who’s read the same essay topic 1 million times,” as Black says. Muir, who used to work as an English teacher, has experienced this from both sides. She credits fan fiction with helping her learn to connect with readers, and in the classroom “being a storyteller is something I’ve always struggled to teach. We don’t give kids the opportunity to be writing for an audience.”

Anne Jamison, an English professor at the University of Utah who has studied fan fiction, sometimes tries to apply its lessons to her teaching, both in college and when she works with younger students. For instance,  with elementary-school students, she finds that fan fiction is a way to get them invested in writing. “I go into a second- or third-grade classroom and say, ‘Everybody start writing stories about Minecraft,’” she says. “They ask if they can keep going through recess, they’re so excited.”

“The authors whom we interviewed unanimously and unequivocally communicated their belief that fanfiction had helped them hone their craft,” Aragon and Davis write in Writers in the Secret Garden. Some felt that fan fiction had taught them things they could never have learned in school. And Aragon and Davis think that the sort of distributed-mentoring community that exists in fan fiction isn’t just useful for improving writing. They mention DeviantArt (an online community for visual artists) and Ravelry (a knitting website) as places where distributed mentoring may also thrive. “If you have this basis of interest-driven learning in a supportive community,” Davis says, “that sets the stage for learning pretty much anything.”

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.