"The Principal and the Pauper"
Season 9, Episode 2

Turns out that, before serving as elementary school principal, Seymour Skinner rocked an awesome leather jacket, had a James Dean 'do, and a "Don't Give a Fuck Attitude" as a biker punk named Armin Tamzarian. It was a far cry from the uptight beauracrat he became, but after the real Seymour Skinner re-surfaced in Springfield, it was time for Armin Tamzarian to ride again. Until he hung up his leather jacket and resumed having a stick up his butt.