One of Josie’s prime dilemmas in returning to school is the attraction she feels toward her English Literature teacher, Sam Coulson. "It’s a dilemma for both characters," says Michael Vartan, who plays Sam. "She really can’t say anything to him about her real purpose there, for fear of losing her job. At the same time, he may be falling in love with someone he thinks is a 17-year-old student."

The obstacles between Josie and Coulson add to the film’s humor. Vartan was able to play both a teacher — a figure of authority — and a romantic lead. "That is a tough balance for an actor to pull off," says Barrymore. "And Michael did it very gracefully."

David Arquette, best known for his role as Deputy Dewey in the two "Scream" films, plays Josie’s brother, Rob, a slacker who peaked in high school and now works at a Tahitian-themed mail outlet. "He was the coolest kid in school who’s never really gone past his graduation day; he kind of stalled out," says Arquette. "Now he’s kind of down because he never fulfilled his dreams."

Having known Barrymore for many years, Arquette says it felt comfortable for him to play her sibling. "I feel very close to Drew; I’ve seen her grow up, so we’ve built a trust and now it’s very comforting to work with her."

The first friend Josie makes during her return to high school is Aldys, the school’s chief nerd and leader of the math team, The Denominators. But Josie’s assignment is to hang with the cool kids, so she has to leave Aldys and her group behind, which causes much distress.

Aldys is played by actress Leelee Sobieski, who received critical attention for her performance as the young daughter of a famed writer in "A Soldier’s Daughter Never Cries." Sobieski also co-stars with Tom Cruise and Nicole Kidman in Stanley Kubrick’s upcoming "Eyes Wide Shut."

"Aldys is not popular at all," says Sobieski. "She’s very smart and doesn’t care what anybody else thinks about her. There are many unpopular kids who can’t stand up to the popular kids, but Aldys is very smart so she can fight back."

Providing sharp contrast to Aldys and the "nerdy" Denominators are the school’s "cool" kids, the leaders of which are three girls, Kirsten, Kristen and Gibby, and three boys, Guy, Jason and Tommy. The distaff members of the cool gang are played by Jessica Alba, Marley Shelton and Jordan Ladd.

The three actresses note that their characters share an impenetrable bond that Josie tries to infiltrate. But as Josie becomes cool herself, the girls start to accept her — and her idiosyncratic attire — and start dressing just like her.

The cool girls also make appropriately stylish fashion statements. Costume designer Mona May says they are totally high fashion. "They know the exact shade of everything," she says. "Their make-up is perfect. Their hair is perfect. The nails match. The purses match. They really dress up for school — every day."

The three chief cool guys are played by Jeremy Jordan, James Edward Franco and Branden Williams. Guy Perkins, played by Jordan, is the non-appointed leader of this group and the biggest heartthrob in school.

For the staff of the Chicago Sun-Times, the producers brought together a talented ensemble of actors. Josie’s best friend at work, Anita, is played by "Saturday Night Live" cast member Molly Shannon. Anita is a party girl who finds herself in some pretty awkward situations. "She’s just sort of wild," relates Shannon. "She’s sort of the office floozy; she just wants to have a good time with the boys." Like Josie, Anita is also looking for love — she just goes about it an a different way.

Josie’s boss at the paper, Gus, is played by John C. Reilly, who is perhaps best known for his co-starring role as Reed Rothchild opposite Mark Wahlberg in "Boogie Nights."

Gus is a man under a lot of pressure from his boss, so it doesn’t help that his underling, Josie, has been assigned a reporting job when she has no previous reporting experience. "Gus has got a soft spot for Josie," says Reilly. "It’s kind of a fatherly relationship, but at the same time he’s got deadlines to meet and a tyrannical boss hanging over him. So he’s a little bit salty, but with a heart of gold."

Gus’ boss, Rigfort, is equally gruff, but few would say his heart is made of gold. "Mr. Rigfort is obsessed with undercover reporting," explains noted actor/filmmaker Garry Marshall, who takes on the role. "He’s a little crazy, and decides he wants to do a story on high schools. He looks around the room and, sees this one girl — Drew — who’s just about the right age, and assigns her the job, even though she’s not a reporter."