"I was always pretty gutsy," she said of her youthful crushes. "It was pretty obvious."
But the movie, which finds the high school valedictorian (Rust) declaring his love for her, did remind her of one childhood moment.
"The biggest crush I can remember was second grade," she said. "I had a crush on this kid who was a really good kickball player. His name was Mike Cassiola."
And, she recalled, the future Hollywood star had some competition for the athletic 7-year-old.
"He told me he had a crush on my best friend at the time, so I told her that he said that he had a crush on both of us, just to make me feel better about the whole situation," she laughed.
Hayden hopes the movie, which has already inspired a wave of YouTube videos of people confessing their own crushes, helps people get over their shyness.
"It's like giving people a free pass to go out there and be gutsy, to give them a kick in the butt to go out and do it," she said. "Some of them are really sweet."
"I Love You, Beth Cooper," is due in theaters July 10, 2009.
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