I have a friend who is a math teacher. He wouldn't care if students called him by his first name, but the administration frowns on it, so he is mainly called Mr. LastInitial.

He introduces himself to players by first names, too.

I am not an administrator or teacher. I *hope* I am more approachable during a game than a principal would be normally.

I am a teacher, and no, I don't let students call my by my first name and they never would. However, I don't put the same restrictions on sports. It is a different setting. I've never had a problem with crossover mistakes. They know in school I am Mr. S and on court I can be Rob. I've not had experience with any disrespect because of this. Perhaps I am lucky but I like to think it's because I've earned their respect. Most of the athletes are ex-students at the HS level, but I do teach a HS music class and have had a current student or two over the years. (never at varsity level - always turn those contracts away)

I would hope all principals are very approachable while still expecting students to call them Mr/Mrs/Ms. The 2 are not mutually exclusive. I am no less or more approachable by the name I give when introduced. My demeanor and personality determine that.

Snaqs, the Mr/Ms FirstName thing is very common around these parts. My kids use that for my personal friends and also for the counselors in their daycare programs through the years. And if a HS school player happened to know my first name, based on my experiences here in Virginia, they would use Mr. FirstName.

In these here parts, students/players address adults as Sir or Ma'am. On the court, officials are usually addressed as Mr. Ref or Miss Ref. They remember our names about as well as we remember the Speaking Captains' numbers.

I forgot to mention that also but I think some people's heads would have exploded. I work on a military installation and the surrounding area has the highest concentration of US military population in the world, so Sir/Ma'am is a regular occurrence around these parts.

I use Sir/Ma'am on coaches all the time, it throws them off when I feel a rant coming on. :D

I won't challenge your statement about the concentration of military there, but it's pretty significant where I work as well. Coaches don't flinch when I refer to them as sir or ma'am.