Cameron Diaz, Jamie Foxx, Quvenzhane Wallis surprise school with 'Annie' sing-along

Cameron Diaz, Jamie Foxx, Quvenzhane Wallis Surprise School with 'Annie' Sing-Along
Cameron Diaz, Jamie Foxx, Quvenzhane Wallis Surprise School with 'Annie' Sing-Along

A middle school assembly took an exciting turn when the cast of Annie surprised them with a sing-a-long they'll never forget.

The fifth and sixth grade students of Warren Lane elementary school in Inglewood, Calif., thought that they were just singing the songs of Annie for a typical assembly, but a couple bars into "It's the Hard Knock Life," they were surprised by their celebrity guests.

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Annie stars Jamie Foxx, Cameron Diaz and Quvenzhane Wallis showed up to accompany the kids, who welcomed them with screams and applause.

The new, contemporary version of the fan-favorite stage musical casts Quvenzhane in the title role: a young, happy foster kid who's also tough enough to make her way on the streets of New York in 2014. Originally left by her parents as a baby with the promise that they'd be back for her someday, it's been a hard knock life ever since with her mean foster mom Miss Hannigan (played by Cameron Diaz).

But everything changes when the hard-nosed tycoon and New York mayoral candidate Will Stacks (Jamie Foxx) -- advised by his brilliant VP, Grace (Rose Byrne) and his shrewd and scheming campaign advisor, Guy (Bobby Cannavale) -- makes a thinly veiled campaign move and takes her in. Stacks believes he's her guardian angel, but Annie's self-assured nature and bright, sun-will-come-out-tomorrow outlook on life just might mean it's the other way around.

Based on the Tony-winning Broadway classic that has delighted audiences for generations, Annie is produced by Will Smith and Jada Pinkett Smith along with James Lassiter, Shawn "JAY Z" Carter, Laurence "Jay" Brown, Tyran "Ty Ty" Smith and Will Gluck, who also writes and directs.

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While landing a role in the movie was a dream-come-true for most, Cameron had to overcome her fear of singing to play the part.

"Trying to sing well is not something that comes naturally to me," said Cameron.

Annie hits theaters Dec. 19.