I had initially planned to have the lecturer address each of his young pupils as "Master [family name]" (that being the--now archaic according to Merriam-Webster--title given to boys too young to be called Mister).
However, I quickly learned that "Master" is also the title given to male teachers and navigators on sailing vessels (the academic usage dates back to the 1380s according to etymonline.com). Now I'm not sure how my lecturer should be expected to address his pupils. I'll bet this has an easy answer, but I'm just not finding it. During what era was "Master" [originally] used as an honorific for young, unwed males?
[slightly edited entry for clarity, but did not remove any text]