Re: asking teachers about titles.
Where I'm currently working, the default title being used for female teachers is "Miss" - that's from staff as well, no matter how many times I say that it's "Mrs". (I quite like the French way of automatically using "Madame" with women of a certain age. I'm told - by my French teacher - that it's now very rare to hear "Mademoiselle" being used with a young woman in France.)
I'm old enough to remember when "Master" was used as the title for a boy, so I don't have a problem with Master/Mr and Miss/Mrs. If people want to use 'Ms', that's fine. I used it for a while myself, but find "Mrs" easier on the ear.
I've come across one case of a man telling pupils (and others) to call him "Mx". In that case, I noticed that the kids were very careful to use his correct title, but couldn't cope with his wish for 'they/them'.
So far as surnames are concerned, in my part of Scotland it was usual for people to refer to married women by their maiden name - even if the surname being used officially was the husband's. Until very recently, it was always the wife's maiden name that went on any memorials and that's what I have on both the memorials to my husband. (We can only rent a memorial at the crematorium, so I've had his details added to the family headstone as well.)