http://www.youtube.com/watch?v=wOENu0fK0uM
Dead Poets Society is known for helping jump-start the careers of Ethan Hawke and Robert Sean Leonard, but it also featured the very first role for someone you wouldn’t expect: 19-year old Jamie Kennedy, who had an uncredited turn as an extra in the film. Kennedy plays one of Robin Williams’ students and he doesn’t get much camera time, but you can catch brief glimpses of him as the guy in the grey sweater at the 2:14, 2:26 and 3:44 marks of this clip.