This article is from the alt.usage.english FAQ, by Mark Israel email@example.com with numerous contributions by others.
This is first recorded in 1749 in the sense "an odd person". It
is *doubtful* that "quiz" came from an alleged incident in which
James Daly, a late-18th-century Dublin theatre manager, made a wager
that he could introduce a new word into the English language
overnight, and hired urchins to chalk the word "quiz" on every wall
and billboard in Dublin. "Quiz" may come from the Latin "Qui es?"
(= "Who are you?", the first question asked in Latin oral exams in
grammar schools), or it may be a shortening of "inquisitive".