It's a time-honored tradition for high school dramas to be populated with actors well out of their teens. Here, then, is a tribute of sorts, assembled by examining each big teen show on the air, then isolating its oldest cast member. Their characters may flirt at parties to the sounds of Lady Gaga and dance at the high school prom to Taylor Swift, but in real life, some of these actors haven't been in school since Kurt Cobain was alive. Who are they?
90210
Oldest Cast Member: Trevor Donovan, 30
Until this season, the oldest high schooler on 90210 was the 29-year-old Michael Steger (Navid), who's actually several years older than the cast member playing his teacher, Ryan Eggold (25 in real life). Then 90210 had to go and add Trevor Donovan, who'll be turning 31 next month. Gabrielle Carteris would be proud!
Gossip Girl
Oldest Cast Member: Jessica Szohr, 24
On most teen dramas, it's usually a male cast member who's the elder statesman. Not so Gossip Girl, where Jessica Szohr holds that title, outranking next-oldest actor Chace Crawford by almost 16 months.
Glee
Oldest Cast Member: Cory Monteith, 27
For a high school show, Glee has an unusually young cast -- 18-year-old actor Chris Colfer (Kurt) could even be a senior in real life. And then there's Cory Monteith, who plays the school's male lead, Finn, and turned 27 before Glee's spring premiere.
The Vampire Diaries
Oldest Cast Member: Paul Wesley, 27
There's always been something unsettling about hundred-year-old vampires entering into romantic relationships with teenage girls, but at least it makes the real age of Paul Wesley (as Vampire Diaries' high-school-enrolled bloodsucker) seem like small potatoes.
The Secret Life of the American Teenager
Oldest Cast Member: Greg Finley, 24
ABC Family hit The Secret Life of the American Teenager has a provocative title, and it's one that may prove educational for Greg Finley (Jack); when he turns 25 next month, it'll have been six years since he was a teenager.
Friday Night Lights
Oldest Cast Member: Zach Gilford, 27
It's a good thing Zach Gilford is wrapping up his stint on Friday Night Lights this season, since the actor's way past graduation age at 27. Still, he wasn't always the wise old man of the group -- until 2008, that was an honor held by actor Scott Porter, who turned the big 3-0 this year.