Few accounts are more gripping than those of people who have lived through harrowing situations. Author Lauren Tarshis has witnessed the appeal of such stories to children firsthand in her day job as group editorial director for language arts for Scholastic’s classroom magazines and editor of StoryWorks magazine (for students in grades 3-6). Seeing kids and teachers gravitate to stories about natural disasters and other dramatic events provided the spark for Tarshis to create her I Survived series, which has sold more than 10 million copies since its launch in 2010. The 10th title, I Survived: The Destruction of Pompeii A.D. 79, was published in late August, landed on national bestseller lists, and has sold more than 20,000 copies so far in outlets counted by Nielsen BookScan. The first-ever hardcover nonfiction companion book to the series, I Survived True Stories: Five Epic Disasters, was released this week.

Each of Tarshis’s tales features the fictional narrative of a boy caught up in a frightening historic scenario, ranging from the sinking of the Titanic in 1912 to the Nazi invasion in 1944 to the Japanese tsunami in 2011. “When I first took over [at StoryWorks] 20 years ago, the magazine was largely fiction, poetry, and plays,” says Tarshis. “That’s what teachers wanted then. But I started to sneak in some nonfiction, narrative nonfiction in particular, about things like the hurricane of 1938 or [the eruption of] Krakatoa. It got an enormous response. Kids loved those stories, and they were willing to wade through complex science or history to follow the plot.”

Back in early 2010, Tarshis, who has also had success with her other published works, had planned to write a third book about her character Emma-Jean Lazarus, star of Emma-Jean Lazarus Fell Out of a Tree (Dial, 2007) and its sequel. But the popularity of the nonfiction stories in StoryWorks was something that kept tugging at her. “I wondered, ‘Where is the narrative nonfiction for younger readers – the books between the Magic Tree House and The Lightning Thief? The bridge books, especially for boys.” Tarshis knew there was a need for these books not only from her professional observation but from her personal experience. “I did not successfully finish a novel until I was in high school,” she recalls. “I felt so shut out of interesting stories. Because of that experience I wanted to try and write about topics that were hefty and make them accessible. I wanted to create stories that I would have been able to access as a kid.”

Over a weekend Tarshis fleshed out her series idea and soon she had a contract for four books. “I thought that would be that, and then I’d get back to my beloved Emma-Jean,” she says. But once the series landed, and garnered both solid praise and strong sales, plans changed. Another factor in Tarshis’s tabling of other projects was the research required for the I Survived books. “I thought it would be a snap,” she says. “Ha! The research tortures me! It’s as much research as I would do if I were writing an adult compendium on any of these topics,” she says. “If you saw my office right now, you’d think I was an Oxford professor of Pompeii studies!”

Tarshis says she spends “three solid months, using all my spare time” reading books on a topic. She then conducts interviews, if she’s writing about a more recent event like Hurricane Katrina. At the three-month point, “I cut off and start writing, though I keep researching while I’m writing, to get more of a backstory for the characters.”

A key aspect of her research, according to Tarshis, is her focus on tiny details. “What is the weirdest thing a person in Pompeii would eat? What were the hairstyles like? What did things smell like? Those are things I like to include,” she says. “I also look at personal narratives and diaries whenever possible, and when I’m done I feel like I’ve gone back in time. None of it comes easily, but I very much enjoy it.”

Kids, teachers, librarians, and booksellers clearly enjoy the fruits of all the hard work, judging by how many of them take the time to praise the series. Bookseller Kathleen March from Anderson’s Bookshop in Downers Grove, Ill., is a fan. “I have a few families that have boys that will only read I Survived. Last month I had been recommending the books to a couple of teachers and they wiped me clean of every copy I had for their classrooms. It’s also my go-to series when working with teachers trying to ‘ease’ them into using fiction with Common Core.”

Some of the most moving notes Tarshis receives come from parents, she says. “They often start with something like, ‘I’m writing to you as my son is in bed, reading past his bedtime, and this has never happened before.’ ” She has received letters from families whose grandparents were Holocaust survivors, thanking her for providing a safe way to explore complicated topics. And Tarshis says she was “overwhelmed” by the positive responses from firefighters following her book I Survived: The Attacks of September 11, 2001.

As is the case for many authors, the letters from young readers range from adorable to powerful. “There are some seven- and eight-year-olds who are little historians, and ask me to write about a specific battle in the War of 1812,” she says. All of this feedback via correspondence and from her visits to classrooms, “inspires me to keep going,” Tarshis notes. “I get great personal satisfaction making a connection with kids.”

That connection with kids helped determine the topic for book 11, I Survived: The Great Chicago Fire, 1871, which is due in March 2015. Earlier this year, on its dedicated website for the series, Scholastic encouraged readers to weigh in and vote on what they wanted the next book to be; the Chicago Fire came out on top.

Though her plate is full with her magazine work and writing two I Survived books per year, Tarshis wouldn’t have it any other way. “I’m set to do three more after Chicago Fire, for sure,” she says. And beyond that? “I could see doing more as long as kids want to read them. We’ll see!”

I Survived the Destruction of Pompeii, AD 79 (I Survived Series #10) by Lauren Tarshis. Scholastic, paper $4.99 Aug. ISBN 978-0-545-45939-6