One Direction,The Roots sing 'Santa Claus Is Coming To Town'

 The boys of One Direction joined Jimmy Fallon and The Roots for a Christmas edition of their Classroom Instruments musical skit Monday.
Dressed in colorful Holiday sweaters Niall Horan, Zayn Malik, Liam Payne, Harry Styles and Louis Tomlinson sat down with Fallon and his musical crew to play and sing a rendition of "Santa Claus is Coming to Town."
The band's performance follows their weekend appearance on Saturday Night Live where they were featured as the musical guest.
The London-based boy band was formed by Simon Cowel after coming in third place on the seventh season of The X Factor U.K. The band's fourth studio album, FOUR, was released on Nov. 17 and currently sits at the No. 1 spot in the U.S. album chat.