Mariah Carey's "All I Want For Christmas is You" is a holiday classic. But when Mariah stopped by Jimmy Fallon's late night studios, they made the song extra special. Joined by Fallon, the Roots and some young helpers, the group did a sing-along using classroom instruments!
What do you think Jimmy is thinking about as he belts out the holiday tune? Leave your suggestions for the thought bubble in the comments section below and we'll keep updating the gallery above! Also, tune in to Showbiz Tonight at 11 p.m. ET/PT this week to see if your comments make it on TV!