Celeb Dropouts Finally Graduate

Nelson's teachers provided Wilson with materials to study while she was on the road, and they assisted with her most difficult subject, math. When it came time for the April 12 test, Nelson said, "She knocked the top out it."

Like Williams, the inspiration for Wilson to finish her education came from her daughter, 7-year-old Grace. "Even though, financially, Gretchen does not need her GED -- she has a corporation that employs about 40 people -- she wants her daughter to be grounded, to understand that education is important, no matter what you do," said Nelson.

Nelson believes Wilson could also be an inspiration to others, and has encouraged her to become a spokesperson for adult education. She said 93 million Americans age 25 and older are without a high school diploma. "People don't realize how vital adult education is," she said. "I told her, 'You speak to that population well.'"

Some might argue that a high school diploma or college degree is not a necessity for a celebrity. "It's not one of the requirements you have to have to become a star," Joe Galante, the chairman of Wilson's label, Sony BMG Nashville, told The Tennessean.

But Syracuse's Clarke sees a correlation between athletes and aspiring stars. Just as athletes are encouraged to get their college degree before turning pro, she argues that aspiring actors and musicians should do the same to prepare themselves for the time outside of the limelight.

Having a college degree also makes celebrities, such as Jodie Foster, Brooke Shields and Natalie Portman, stand out from their peers, Clarke said. "There's an added recognition, an added value."