The person who most seriously doubted she would ever pull it off was Karr herself. “I probably threw away 500 pages before I started saving pages,” she says, sitting in the upstairs study of her home in Syracuse, where she teaches creative writing and English at Syracuse University. “I’m a very bad writer,” she declares with a straight face. “My first drafts are always like, ‘I am sad. Then I went to the store. Then I came home and went to sleep’.” She smiles, waits a beat and then drops in the perfectly timed kicker: “But I’m a pretty good rewriter.”

This is Karr all over, modest one minute, cocky the next. If you suggest that her writing captures the powerlessness of children as well as Frank McCourt’s, she volleys with, “Yeah, but I did it before he did.” But no one could be more generous with praise. Every other sentence hails a writer she admires, from Harry Crews to Elizabeth Bishop. It’s the same with religion. While she’s a fervent Catholic, she admits, “I feel stupid when I talk about it. But when I don’t, I feel false.” Even her house sends mixed signals: a modest two-story on a modest tree-lined street, its porch is painted purple, and inside, a typical bookcase forces a biography of W. B. Yeats to share space with Puff Daddy and Eminem CDs. “Dev [her 14-year-old son from a former marriage] is teaching me about rap,” she says with a grin.

Rake thin and fit at 45 (she works out in a boxing gym), Karr is perfectly at home with her contradictions. At 11, she wrote in a journal that her ambition was “to write 1/21 poetry and 1/2 autobiography.” (With three books of poems and two memoirs under her belt, she’s almost on schedule.) The problem with “Cherry” was finding herself in the story. “This book is about the way you try out being different people. You’re trying to be a cheerleader and then you’re trying to be an athlete or you’re trying to be a hippie. So to write out of one voice or one posture is often false.”

The toughest stretches were the parts about teenage sex. “There’s no language for writing about girls’ sexuality. All the imagery in the culture is so reflective of how guys feel. It’s why women haven’t written about this thing.” In the book’s most erotic scene, a barely teen Mary gives her boyfriend a massage while he and his dad watch “Monday Night Football.” Then she rushes home to fantasize. “The fact of that body is too carnal for this sharp luminosity in me,” she writes. “Instead I picture John leading me under the spangled lights of this mirrored ball for a slow dance.” Discussing this passage, Karr says, “The things that had erotic attachment for me were things that the culture doesn’t perceive as erotic. They were all sort of in the courtly mode, really. I think most little girls are like that.” “Cherry” gives those girls a voice.

Karr’s pondering a book about the deaths of her parents, but she’s not sure she’ll ever write another memoir. “Obviously, if the publishers throw enough money at me, they’ll be able to talk me into it. But I have to have something to go on. I can’t just take the money. That’d be too nerve-racking.” But plainly anything nerve-racking is Karr’s brier patch, where she can strike sparks off disparate notions that don’t make sense together in any hands but hers. So please, lady, just take the check.