The first part is a nice little soulful cover of FM's "Rocketeer," but the real gem is the second half of the video, where they sing a not-so-confident rendition of "Teenage Dream," at the request of the audience.
It's fairly obvious they don't know the song very well, and were pretty much winging it... but they did it for the kids. Lots of doo dum doos and made-up lyrics. Good stuff. I think it's a lot more amusing than if they actually knew what they were doing.
(This might be the only audience where the violin solo gets the biggest screams.)
