Photos by flipchip / LasVegasVegas.com · CC BY-SA 3.0

A stand-up comedian who created and starred in Welcome Back, Kotter (1975–1979), playing a Brooklyn teacher returned to mentor the kind of underachieving students he once was — a show that launched John Travolta's career. Kaplan later left show business for a second career as a professional poker player and television commentator.