I don't really watch Jimmy Fallon's Tonight show except every once in while. It isn't because I dislike him, it is really just a matter of my no longer watching regular television. I just watch 3 shows: Elementary, Game of Thrones and Penny Dreadful. All of them I catch On Demand since I don't even watch these shows during their regular run time.
Anyway, I stumbled on an archive of old Jimmy Fallon skits from his show and I have to say the skits of him playing a snotty little 13 year old named Sara are hilarious. This clip is a music video made of his character Sara and friend Mir.i.am (played by Will.i.am).