Jessica Lowndes lightly covered her winter bikini body on the set of "90210" yesterday. The smiling actress was barely covered from behind as she walked to her trailer.

Jessica and her co-star Matt Lanter are working with to help homeless teenagers. The fourth annual "Jeans for Teens" campaign hopes to deliver its one-millionth pair of jeans to teens in need.

"This is something that teenagers can do themselves," said Lowndes. "They don't need to give money. They literally just need to go through their closet and make someone's day by donating to young person in need."

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