Director Lee Hirsch has a simple goal for the documentary "Bully," which opens Friday in Atlanta.

"Change the world," he said during an interview. "Nothing minor.

"The message here is everybody can be part of the movement," Hirsch said. "Everybody can be part of change. As creative as kids are at bullying, they can be as creative in intervening. I feel like the whole movie was an act of intervention."

The film, which last week had its rating lowered from R to PG-13 after a campaign by supporters, shares the stories of bullied children in various parts of the country, including Murray County, Ga., where 17-year-old Tyler Long hanged himself in 2009. His parents have sued the school system, saying their son had been bullied by other students while school employees "acted with deliberate indifference," according to the lawsuit. The school system's court documents filed in response to the Longs' suit disputes their claims.

"This movie is close to our hearts and soon you'll see why," Tina Long (Tyler's mom) told the audience at an advance screening hosted by B 98.5 at the AMC Phipps Plaza on Monday.

The lights dimmed and soon home video footage of Tyler filled the screen. You see him as a toddler, then as a youngster learning to ride a bike, followed by a view of his grave site. Even before the movie's title appeared on screen, sniffling could be heard throughout the theater.

"I hope (the movie) does shock people to some degree," Tina Long told the AJC. "I think Tyler would say, ‘Finally. Finally, people see it.' I think it’s much easier to ignore the child being bullied than it is to deal with the bullies."

Hirsch, whose work premiered at the 2011 Tribeca Film Festival after being filmed during the 2009-2010 school year, said he was bullied as a child. He most identifies with Alex Libby, the sweet-natured middle schooler who is shown being repeatedly tormented by other students.

"We met Alex on the very first day of school," Hirsch said. "I could just feel in my bones that he was probably bullied."

The Iowa school district where Alex was a student at the time granted film crews access, and students are shown slapping, punching and choking Alex on the school bus, apparently indifferent to the cameras recording the action.

"They got very used to me being around," said Hirsch who shared the footage with school officials and Alex's parents mid-project, concerned about the child's safety. "We became very uninteresting very quickly. Kids felt like they had the sense that they could bully Alex, that it was okay."

Now a freshman in another school district, Alex has told CNN's Anderson Cooper that “Life’s pretty good. I have good grades, tons of friends and my school is amazing.”

Hirsch beamed at his former subject's progress.

"To see him now, smiling from ear to ear, from such a dark state when we met him, this is such an extraordinary young man," Hirsch said. "Now he’s happy, confident, making great grades."

The Longs and an Oklahoma couple whose son also took his own life, who have no such happy ending, have become dedicated to the anti-bullying cause. The film shows them gathering with families at rallies, speaking out and supporting each other.

"We could have stayed in our house and not said a word," Tina Long said. "I’m not sure how that would help anybody."

After the Atlanta screening on Monday, the Longs took comments from the audience.

"I still have chills on my spine," said Vanessa Holmes, who brought her children Elijah, 9, and Shamara, 13. Both attend Fulton County schools. Elijah said other students are not mean to him.

"They're not mean anymore," said Holmes, who says she's met with school officials in the past about bullying incidents.

But Shamara said she related all to well to the film.

"There was this girl at lunch, they were calling her names, pulling her hair," she said. "They thought it was funny so they kept going. I took her to another table with me. I said, ‘don't listen to what they said.'"

When asked when this had happened. She answered, "Today."

Movie preview

"Bully" opens Friday in Atlanta at the AMC Phipps Plaza, Landmark Midtown, Lefont Sandy Springs, Regal Town Center and AMC Mansell Crossing theaters. It is rated PG-13.