KRISTY is a softball player and a dedicated tomboy; she's bossy sometimes, but then again, she's also the one with the good business sense. Claudia is hip, the kind of girl who rocks stirrup pants with a tuxedo shirt and isn't afraid to wield a power drill to turn found objects into earrings. Sleek Stacey, a former child model, is that intimidatingly popular girl from high school who, even as you grow up, remains the most beautiful girl you've ever seen up close. Dawn is the obvious California import, with her long blonde hair, faded blue jeans and bordering-on-smug environmentalism. Quiet, modest Mary Anne is a good listener, but also kind of a crybaby.

Back before Bella met Edward the vampire or Gossip Girl started a blog, there was The Baby-sitters Club, a young adult book series about a group of girls who ran a business and had each other's backs. Today's preteen readers have moved on to sexier subject matter and yet, for a book series that's been out of print for a solid 10 years, The Baby-sitters Club series has a huge, wildly devoted following—of 20- and 30-year-olds.

The series, which ran from 1986 through 2000, was created when children's book publisher Scholastic realized that there was a market eager for books about baby-sitting. The plots would never fly today—a group of 13-year-old baby-sitters who could solve the occasional mystery on the side—but the cast made up for what the plot lacked.

"I was definitely an obsessed fan," says Donica Sharpe, the blogger behind the SMS Cafeteria, so named for the fictional Stoneybrook Middle School where the baby-sitter girls ate lunch for 10 years. "For me, the BSC books are nostalgic. They're a throwback to a time and place where we weren't on the computers all the time, weren't as technology obsessed."

While author Ann M. Martin declined requests for a book series about the girls' older lives and left them stuck in a junior high time-space continuum, they have nonetheless grown up vicariously though their fans.

McSweeney's Internet Tendency, the snarky blog arm of the independent publishing house, suggested several titles for a hypothetical "The Baby-sitters Club: The College Years," such as Claudia and the RIAA Subpoena, Kristy's Softball Friends Don't Buy It That She's Dating a Dude, and Mary Anne Narcs On Her Roommate.

On her What Claudia Wore blog, Kim Hutt revisits the character's outrageous outfits and DIY jewelry one book at a time. When asked to choose between Mary Anne or Claudia as hypothetical roommates, Hutt blogged, "The first time I came home and [Mary Anne] was watching a Lifetime movie and weeping, I would have to be all 'You're out, woman!' so it probably wouldn't work. ... If [Claudia] was late with the rent, I bet she'd be all 'I'm so sorry! I made you this necklace out of perler beads and Polly Pockets!' and I'd fold immediately. Also she'd wanna take bong hits and watch television while making collages out of old tabloids."

Every member of the BSC has a least one regularly updated Twitter account, with #babysitterhaiku as a trending topic and Dawn sending enviro-conscious reminder tweets like "Snack break: carrot sticks and all-natural peanut butter. Need to refuel—saving the world is hard work!"

So when Scholastic relaunched the series by releasing a new prequel, The Summer Before, in April, along with a rash of paperback reprints, the BSC-centric corner of the Internet exploded.

The reissued series—with showy new clip art covers—is being targeted at a younger demographic than the original release, based on the assumption that preteens who have been steeped in vampires simply won't be interested in an innocent series about baby-sitting. Meanwhile, references to cassette players have been updated to iPods, cell phones have been added and Stacey's bodacious signature perm has become merely an "expensive hairstyle." Baby-sitting rates have gone up. And it is these changes that have met with the most vehement criticism from invested older fans.

"I'm glad you're reading and all, stupid Internet generation," writes blogger and former reader Nora Leah Sherman. "But these aren't bastions of fucking literary glory. They're books about teenage girls and I am sad that we have to fucking SPOON FEED them to you so that they are relevant to your lives (OMG WHATS A WALKMAN????)."

Ultimately, whether they are carrying cassette players or MP3 players, the BSC girls face the same enduring challenges of early adolescence as any generation: Stacey explores crushes on older boys, Mary Anne struggles to assert independence from her overprotective father and all the girls learn about building and keeping friendships.

"There are so many books out there that involve sex and drugs for youngsters that don't really have a good message," Sharpe says. "There's a lot of drama and fights in the series, but everything worked out in the end, and the message of true friendship remained. Their impact is evident in the multitudes of fans who grew up on the series who are now blogging and discussing the books on various sites and message boards. I have a friend who is a teacher and she has the entire series in her classroom."

After all, cultural is cyclical. The '90s tweens revived '70s velvet shirts and flared jeans while poring over then-cutting-edge BSC books. Today, that first generation of BSC fans is settling down to have families; many of them are going to want to introduce their daughters to the baby-sitters. And that is exactly what Scholastic is banking on.

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