Idina Menzel stops by the Tonight Show Music Room to perform the Oscar-winning song “ Let It Go” from Disney’s “Frozen .”  The unique thing about this performance is that the song has a new accompaniment – composed from musical instruments that you would find in a classroom.   Jimmy Fallon and The Roots created an impressive re-imagining of this Oscar-winning song.  My favorite part is the instrumental breakdown leading up to the bridge.  It’s at that moment that you realize