Donovan, Agron, Szohr, Cassie, and Monteith in Op's Fall 2010 campaign. Photo: Larry Bartholomew

To promote its Fall 2010 "Back to College" collection, Op has re-enlisted the help of its Spring campaign stars, "Gossip Girl" actress Jessica Szohr, singer Cassie, "Glee" stars Dianna Agron and Cory Monteith, and Trevor Donovan of "90210."

For the new ads, the somewhat unlikely group (we're pretty sure none of these stars actually attended college) hit the UCLA campus, where they made like perky university students, playing in dorms, eating popcorn, and watching movies while dressed in Op's "new vintage" style of casual flannels, tees, and denim with a worn-in feel.

"Sometimes [it's hard] being young and trying to come into your adulthood without a lot of money," Szohr says in a behind-the-scenes clip from the shoot.

"When you're going to school or working a couple of jobs to make it, with Op you can still fit in in this fashion world without having to spend so much money on these big designers.

"I think that's great because with a show like "Gossip Girl," there are very few people that can have those $3,000 bags and $2,000 sweaters. I grew up not in that world at all. [With Op] you can be in this cool fashion-hip world, but it's affordable."

Agron, another promising member of young Hollywood, concurs.

"I love this stuff because I'm very much into men's clothes on women," she says. "Typically, plaid and collared shirts are thought of as masculine, but I really like them."

The new campaign will roll out this August in magazines such as Teen Vogue, Seventeen, and Cosmopolitan. The clothing will be sold exclusively at Walmart, where Monteith once worked as a greeter.

"Sometimes I like to go back and see how time has passed," he says. And now, no doubt, see how far he's come.

In other fashion campaign news, see who's starring in the Esprit ads.