1. Sandra Bullock

2. Fergie

3. Alicia Silverstone

4. Amy Poehler

5. Cameron Diaz

6. Halle Berry

7. Jessica Simpson

8. Kelly Ripa

9. Madonna

10. Megan Fox

11. Meryl Streep

12 Reese Witherspoon

13. Renee Zellweger

14. Sally Field

15. Snooki

Take a look at the Top 15 celebs who were once cheerleader when they were at school.In the late '70s and early '80s, the actress was a cheerleader at her Arlington, Va. high school before earning a degree in drama at East Carolina University in Greenville, N.C. After graduation, Bullock moved to New York where she worked as a bartender, took acting classes and scored her first major film role,, ten years after putting down her pom poms.At her Hacienda Heights, Calif., high school in the early '90s, she went by Stacy Ferguson. But we know her now as Fergie! The pregnant Black Eyed Pea had plenty to cheer about in high school: As a straight-A student and spelling bee champ, Fergie had already spent four years onbefore high-kicking on the sidelines.In the early '90s, Silverstone was both a cheerleader at her San Mateo, Calif., high school and a budding actress, becoming an emancipated minor at age 15 so that she could appear in the sexual thriller,. (She went on to win two MTV Movie Awards in 1994 for her performance.)Thestar (who's also writing a memoir) sported hair with height as a cheerleader for her Burlington, Mass., high school in the late '80s.Before she had audiences cheering for her on the big screen, Cameron Diaz was the one doing the cheering at her Long Beach, Calif., high school.In the early '80s, Halle Berry was already a star as a student at an all-white school in Cleveland, Ohio. As captain of her cheerleading squad, class president and editor of the school newspaper, Berry performed well in any role. "[Doing] all those things helped to make me feel a sense of empowerment," the star ofsaid.Jessica Simpson was a cheerleader and homecoming queen before dropping out of her Richardson, Tex., high school at age 16 in 1996. Eager to pursue her singing career, the talented Simpson was still subject to bullying: "I quit cheerleading because I didn't know what I was cheering for anymore!"Kelly Ripa, (whosecohost, Michael Strahan, is a former football player for the New York Giants) was so inspired by her time as a cheerleader at her Voohrees, New Jersey high school in the late '80s that she decided to produce a TV series about the sport last fall! Ripa and her husband, Mark Consuelos, co-produced, a reality show that followed around a competitive New Jersey cheerleading squad.Before she became a "," Madonna was a straight-A student and cheerleader at her Rochester Hills, Mich., high school in the mid-70s. Almost four decades later, the boundary-pushing singer would don a much skimpier uniform to play the part of a cheerleader for her performance of "" at the 2012 Super Bowl halftime show.In, Megan Fox played a posessed, murderous cheerleader. But she looks much too innocent for that in this photo from her sophomore year of high school in Port St. Lucie, Fla. As a real-life cheerleader, Fox claims "everyone hated me, and I was a total outcast."Three-time Oscar winner Meryl Streep was the picture perfect cheerleader at her Bernardsville, N.J., high school in the late '60s. "She was beautiful," said Streep's friend, Susan Castrilli. "Everybody loved to sit there and watch her with her short skirt jumping around."In the early '90s, Reese Witherspoon stole the spotlight as she climbed to the top of the cheerleading pyramid at her Nashville, Tenn. high school.They loved her for the woman she wanted to be and the woman she almost was! Renee Zellweger wore a lot of hats at her Katy, Tex., high school in 1987: gynmast, cheerleader, drama club member.Even thoughactress Sally Field was flying high as a cheerleader in L.A. in the early '60s, it was her school's drama department that really made an impact. Field recently revisited her alma mater and confessed that the school's theater program "quite simply saved my life" and was the only place where she could "most truly and absolutely be me, where I lost myself and found me."Snooki has been very vocal about her time as a cheerleader in Marlboro, N.Y. The formerstar struggled with bulimia and anorexia before graudating in 2005, saying, "I was a cheerleader and you had freshman girls coming up that were so tiny."(Photos: Seth Poppel Yearbook Library , via iVillage