Remember when you were a kid and 40 felt old? Not anymore! You would never know these youthful stars are hitting such a milestone this year! (40 is indeed the new 20… or at least 29.) So take a look at these childhood photos and see if you can guess which celebs are turning 40 in 2012!

Then they were just high school students, the pretty and the popular, roaming the halls of West Beverly High, but now, after a decade and a half past “graduating” from teen stars to full-fledged adult actors, Snakkle looks back the cast of the original Beverly Hills, 90210.

Jennie Garth spent her late teen years growing up on television, starting with an appearance on the TV show Growing Pains in 1989 before becoming a breakout star on the hit series Beverly Hills, 90210. While she’s starred in many television movies and other series, she’s also expanded her roles to wife, mother of three daughters, and, now, single mom living on a farm in her own reality TV show. Garth has accomplished a lot in her 40 years, and Snakkle wants to celebrate with her!