Question: is matt damon singing scotty doesn't know

Answer: Yes, In the film EuroTrip, Scotty (Scott Mechlowicz) is dumped by his girlfriend Fiona (Kristin Kreuk) for the lead singer of a band (played in the film by Matt Damon). The band performs the song at a party Scotty is attending and is praised by many characters in the film (including Scotty's parents and eventually Scotty himself) as being ``catchy.'' The song becomes something of a popular phenomenon, appearing on the radio and across the world; in Bratislava, the song has been remixed and is playing in a popular nightclub. By the end of the film, it has become so widespread and popular that Scotty's best friend Cooper is able to use it as his cell phone ring tone.