LOS ANGELES—Getting attention in high school can be tough when you’re a so-called nobody, as lead character Olive Penderghast discovers in the teen comedy Easy A. And competing for that role against almost every young female American actor should have been even tougher.

Yet 21-year-old Emma Stone, best known for her work in Zombieland and Ghosts of Girlfriends Past, landed the plum role after director Will Gluck auditioned her and asked her to submit an iChat filmed on her laptop webcam.

“It’s so different and unique from anything I’d read before, and there’s so many messages throughout it and it’s not speaking down to anybody,” the affable Stone says in a Beverly Hills hotel room. “I just thought Olive was such an amazing character, and [screenwriter] Bert [V. Royal] had really fleshed her out so much in the script that just trying to bring her to life was the only challenge. Sometimes you read a character and you think, ”˜Oh, I could go a million different ways with this.’ But that wasn’t the case with Olive. She was who she was.”

In the Scarlet Letter–inspired film, which opens in Vancouver next Friday (September 17), Olive is an average high-school student whose life tweets out of control when she fakes sexual experiences with male students to help her and them improve their social status.

In real life, Stone only attended one semester in a Catholic high school; she was primarily schooled at home and moved from Arizona to L.A. with her mother at age 15 to pursue acting. Her gamble paid off as she won roles on TV series such as Drive and The New Partridge Family. Her film career started with Superbad, and she recently wrapped production on Crazy, Stupid, Love with Steve Carell and Ryan Gosling. She is currently filming The Help, which is based on Kathryn Stockett’s bestseller set in the 1960s Deep South, and she is doing voice work for The Croods alongside Ryan Reynolds and Nicolas Cage.

Stone is effusive in her praise for her Easy A costars Stanley Tucci (The Lovely Bones) and Patricia Clarkson (Cairo Time), who play Olive’s ultracool, comically candid parents and provide an essential underpinning for Olive’s radical journey.

“The parent characters were written very funny in the script, but Patty and Stanley came in and just blew that all out of the water,” she says. “They were so unbelievable. I was so grateful to them, selfishly, because they made Olive make sense. It made that character and the way she is and the way she makes decisions and how confident she is in knowing the truth herself, regardless of what other people believe, until it starts to hurt people.”

Stone says her own parents, although not quite as liberal as Olive’s, were “miraculously similar” in their parenting style. “They always would let me make mistakes, and their biggest role was if you”¦tell the truth, you will never be punished, and if you lie, the punishment will be huge”¦which creates a really open, honest relationship, because you know you won’t be in trouble for making mistakes.

“Kids are going to make mistakes,” she adds, “and if you scare them into lying about it, it’s going to be a tough road, I guess.”