A satirical exploration of the female cliques within the school parental community, The Hive is female-focused in the same way that Fever Pitch - her brother's love letter to Arsenal - is blokey.
"It's not very fashionable to say it but I've got two boys and two girls and their social lives and the way that they interact with their friends is completely different," says Hornby. "Girls have these great passionate friendships and these awful bitchy episodes, which just doesn't seem to happen with boys.
"In the same way, boys aren't completely sharing their feelings all the time in the way girls are. They have friends and they get on with one another but they share different information and tend to come together over external passions like a football team."
Indeed, The Hive grew out of a bonding session with her teenage daughter - "who wasn't having a particularly nice time at school" - which involved watching the 2004 comedy Mean Girls, starring Lindsay Lohan and Rachel McAdam as a pair of feuding adolescents.
"The movie's kind of like an instruction manual," laughs Hornby, who was so intrigued by its theories about female behaviour that she tracked down the book it was based on, Rosalind Wiseman's Queen Bees and Wannabes.
"I thought it was a novel but it's not that at all. Rosalind Wiseman is a psychologist in the US, who has assembled all these case studies of what happens in American middle schools. But it could be anywhere as it's absolutely universal. And then I decided to invert it and make it about the parents."
Set in a fictional school, St Ambrose, the novel centres on Queen Bee Beatrice whose supposed dominion over everything from car boot sales to the lunch ladder is challenged by the unassuming Rachel.
"It's very much like a hive," says Hornby of the social network's similarity to a real bee hive. "You look in and there are people rushing around as if they're fantastically important. It's all rather meaningless to an outsider. But when you're inside, you can see everybody is playing their part and it's all knitting together into a proper coherent whole."
Based in rural Berkshire, Hornby visited her local beekeeping association during her research. "I couldn't believe the parallels but once you've got your eye in you can see it's exactly how we operate. It's a completely female society in a hive so it was very interesting to look at it."
Divided into three sections that mirror the British school calendar, Hornby's writing routine was governed by the subsequent restrictions.
"I couldn't write it during the holidays because I had the children, so I was definitely living it," she says. "I would drop my little one off in the morning, come home and start writing but it would have to stop at 3pm as I had to go and get him. But once I'd got that structure and had decided the action would only take place within the school terms and around school business, it became much easier as there weren't things happening in the holidays or just with the families."
Although the novel takes place within a typically British educational institution, Hornby believes it is just as relevant in other countries.
"I'm sure it's exactly the same in New Zealand," she says. "It's one thing we all have in common. There are all different kinds of schools in different sorts of places and we all have very different experiences while we're there, but we are all shoved through like sausages. I thought I was just writing a little English book but an American production company has bought the movie rights and it's also been sold in Brazil, South Korea and all over Europe."
But Hornby insists the novel is not simply about the school experience.
"You could extrapolate that plot and put [it] in a woman's office or a book group and somebody told me the other day it was just like their dog-walking group," she says. "It's just about the group politics you get with a certain number of females."
The Hive (Little, Brown $37.99) is out now.