고교얄개(1976) / Yalkae, A Joker In High School (Gogyo-yalgae) (1976)

A chronically troublesome but big-hearted high schooler spends his second year picking fights, chasing a girlfriend and, when a classmate's hospital bill comes due, quietly getting hurt trying to cover it himself. A coming-of-age comedy that trusts its delinquent hero more than his teachers do.

Why it's free: Free on the Korean Film Archive's own channel; the national archive holds and restores the prints it publishes.