Kelly Kapowski
is all grown up!

Tiffani Thiessen, who's celebrating her 40th birthday today, is still the spitting image of the bubbly cheerleader from "Saved By the Bell."

The brunette beauty caught her big break at the age of 15, landing the life-changing role on the hit NBC series.

After starring on the high school sitcom from 1989-1994, Tiffani went on to play Valerie Malone on "90210" from 1994-2000 and currently stars on "White Collar" as Elizabeth Burke

In 2005, she started her own production company, Tit 4 Tat Productions. The company's first project was also Thiessen's directorial debut: a short film called, "Just Pray."

The actress is now happily married to Brady Smith and has a beautiful 3-year-old daughter named Harper.

Tiffani wasn't the only star to steal the hearts of teenage boys in the '90s -- click "Launch Gallery" above to see her "Saved By the Bell" costar Elizabeth Berkley, along with Jessica Biel, Jennifer Love Hewitt, Pamela Anderson, Carmen Electra and more leading ladies who got their big breaks over 20 years ago!

Hot Videos