Winnie Cooper as You’ve Never Seen Her Before

Winnie Cooper as You’ve Never Seen Her Before

Little Winnie Cooper from "The Wonder Years" isn't so little anymore!

Danica McKellar is now 38 years old and looking sexier than ever. The actress was spotted on the set of Avril Lavigne's new music video for her single "Rock N Roll" in Palmdale on Thursday in an unexpected ensemble.

McKellar sported orange pumps, blue fishnets, red metallic shorts, and a cropped top and denim jacket, giving a whole new meaning to the term "hot mess" — especially when it comes to her abs! But McKellar is a smart woman. With her degree in math, we're sure this is a calculated move.

It seemed that outrageous costumes were the theme for this music video because newlywed Lavigne sported a unique ensemble as well. With huge boots, a short camouflage miniskirt, a forest-green bustier, and a helmet, her look really was all over the place … and not in a good way.

But even though their get-ups might have been a little crazy, Lavigne and McKellar seemed to embrace their looks and enjoyed spending time together on set.

The "Wonder Years" star even posted a Vine video showing off her new look and also tweeted about the experience: "Just had the best time shooting @AvrilLavigne's new video. And she is so sweet and fun! Made me feel like a rock star. ;)"

To see pics of the grown-up child star on set, check out the vid, and be sure to watch "omg! Insider" on TV tonight for more of the latest in entertainment news.

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