I'm 20, and for a friend's 21st birthday we did one of these minus the wine. We all dressed in our suits or nice shirts, fedoras, slinky dresses, etc. The guys had red roses on their plates when they arrived, and the girls had white ones. We ate a four course italian dinner while Frank Sinatra and similar music played in the background. Fake, terrible italian accents were attempted, and we all loved every minute of it.
I know that teenagers are sometimes a bit more uptight about acting enthusiastic about something so goofy, but it was the most fun party I've been to. Afterwards we all danced to pre-sixties music. The whole event lasted three or four hours.