Shailene Woodley Donating Hair for 'The Fault in Our Stars'

Shailene Woodley

The actress is cutting off her long locks this weekend as she prepares to play a teenager with cancer, but she's giving them to a good cause.

Shailene Woodley's long locks are about to be a thing of the past, but she's donating them to a good cause.

The actress, who's about to play a teenager with cancer in the movie adaptation of the best-selling YA novel The Fault in Our Stars, is chopping off her hair this weekend, the book's author John Green explains on his Tumblr.

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She'll be donating her hair to Children With Hair Loss, an organization that provides human-hair replacements to kids who've experienced hair loss due to various medical conditions, Green adds.

This was entirely Woodley's idea, the author says, adding he's not even sure Fox 2000, which is releasing the film, knows about it.

Green has encouraged fans to join the actress and signal their support using the tags "hairforhazel" or "itgrowsback."