Eric Stoltz was 15 in The Grass Is Always Greener Over the Septic Tank when he played the character 'Steve Benson'.
That was over 46 years ago in 1978.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 62, and has starred in 86 movies in total, 86 of those since The Grass Is Always Greener Over the Septic Tank was released.
In The Grass Is Always Greener Over the Septic Tank, I think Eric Stoltz looks: