Video: Mariah Carey, Jimmy Fallon & The Roots - "All I Want For Christmas Is You" Live On Classroom Instruments

Mariah Carey, Jimmy Fallon and The Roots play "All I Want For Christmas" live on classroom instruments backstage at LNWJF during Mariah's appearance on the set last night. In case you're worried about what happened to the little kids whose instruments they jacked for this performance--don't be, they're fine. For proof of life watch below and pay special attention at :35 seconds in. And by the way, you can purchase Mariah's holiday LP Merry Christmas II You on iTunes now.