It all started with a box of "Sweet Valley High" books.

“A few years ago, I was feeling kind of exhausted about being an adult,” said author Gabrielle Moss, speaking Thursday on CTV’s Your Morning. “And as many of us do when we’re exhausted about being an adult, I went on eBay and I was like, I’m going to blow some money on something from my childhood.”

The books not only gave her a “nostalgic flashback,” but inspiration for a new project.

Her book, "Paperback Crush", is a history of the waves of young adult and children’s novels that poured into the market in the 80s and 90s, focused on plots like friendship, romance and sibling rivalries. Series for young girls such as "Sweet Valley High" often contained so many volumes that they filled entire library shelves all on their own.

“I started getting interested in the ways these books shaped us, for good and for bad,” Moss said. “I think they made an impact on our young lives and the way we thought about being an adult and being a woman in a way a lot of people haven’t examined.”

These novels stood in contrast to the more serious topics handled in the YA of the 1970s—a decade defined by Judy Blume’s landmark children’s novels—and took residence in the minds of tweens before "Harry Potter" or the blockbuster dystopian trilogies of the 2000s came along. But although the concerns of the YA novels of the 80s and 90s may seem trivial to us now, Moss says it was their very pulp-absurdity that captured their young audiences.

“I do think it was because they took our concerns so seriously,” she said. “They treated things that felt like the end of the world, when you’re that age, like the end of the world!”

"The Baby-Sitters Club," another series that was immensely popular at the time, dug into the “high drama” potential of being “a sophisticated twelve-year-old who is being entrusted with the lives of small children,” Moss said. “What a fantasy!”

She pointed out that this series also focused strongly on the female friendships of the young protagonists.

“I think a lot of us took those ideas with us as we grew up,” Moss said, “and that’s why we think friendships are important to the level our mothers’ generation might have not.”

But these wholesome stories did not come without a darker side.

“There are a lot of problematic things about this era, especially on the diversity front,” Moss acknowledged. “Almost all of the characters in these major series are white, everyone’s heterosexual, people seem to be pretty rich—it’s very different from YA right now.”

She said that in her research for "Paperback Crush," writers of colour who “tried to make a dent” in the market struggled. “It was very tough for them to break through, and so that is a negative impact of these books,” she said.

Although some of the books of this era, such as "The Face on the Milk Carton," introduced tropes like “stranger danger,” and kidnapping to the YA genre, Moss said that current YA covers deeper territory now, with often “much more extreme danger.”

Even if YA has moved back into grittier territory, for the thousands of adults who once wiled away afternoons with a flimsy "Sweet Valley High" in hand, this era will always have its charms.

At least, it still does for Moss.

“It was a dream to have an excuse to go back and read all of these,” she said.