Reese Witherspoon and Disney are supporting First Book with this Instagram campaign (and it won't cost you a cent). 

Woman Taking Selfie on smartphone
Credit: Silke Woweries/Getty Images

If you’ve ever followed along with Reese Witherspoon’s book club, then you already know that the star loves a good book. And yesterday, Witherspoon announced on Instagram that she’s teaming up with Disney and A Wrinkle in Time to support an important cause: providing books to children in need.

Want to help the cause? Witherspoon explains how easy it is in the caption on her post: “Post your #shelfie with the hashtag #MagicOfStorytelling and @Disney will donate a new book to a child in need through @firstbookorg ! 📚” It’s that easy—and it won’t cost you anything to contribute. If you're wondering what a shelfie is, check out #MagicOfStorytelling for inspiration. It typically means a photo of a beautifully styled shelf (and there are plenty of those that have been submitted), but if you don’t want to spend time revamping your bookshelves, don’t worry—the official entry rules ask for a selfie taken with a book. And it doesn’t have to be A Wrinkle in Time, but any title of your choosing. Then, just remember to tag it #MagicOfStorytelling, and Disney will donate a book to First Book, a non-profit that provides books and other educational resources to kids in need.

While the idea that our selfies could help provide children with new books is all the incentive we need, Disney is also having a Magic of Storytelling sweepstakes, and for every entry, Disney will donate a book. The grand prize is a five-day, four-night vacation to Aulani, a Disney resort and spa in Hawaii, so get your entries in ASAP. There’s a limit of one entry per person per day, but it runs through March 31, so you still have dozens of chances—and the chance to donate dozens of books.