How to handle irrelevant questions about high school during an interview for a software engineering role?

We cannot know what the interviewers will be looking for. As you said, anything you did a quarter of a century ago in highschool is completely irrelevant.

That leaves only one thing to get out of those questions: your behavior.

Again, we don't know what they are looking for. So assuming you are looking for a good job where they look for nice, truthful people:

Be nice. Be truthful. Be cheerful. Admit your own mistakes if you made any (who didn't in highschool?). Don't sweat it.

The only negative thing would be a negative reaction on your part, for example not answering softball questions about highschool or getting nervous over questions that do not really matter.

As long as interview questions don't fish for protected data ("are you pregnant?" comes to mind), they are free to ask you everything. And you are free not to answer. But if you refuse information, this will be seen as a strong red flag. Do you have something to hide? Were you an axe murderer during your high school years?

I'd try to get done with that as fast as possible. Give them a very short overview about that time, no need to go into detail. I don't expect that they will press you for details. A good HR person should realize that it has no relevance. If they try to grill you because of unrelated coursework, a lesser career drive during your twenties or your higher age, focus on the positives: You have tried different career paths and industries and gained a lot of life experience from it. And since 12 years you have settled for the software industry, because you found what you truly love here.

If you studied languages in high school, this is an excellent thing to talk about in your interview.

Computer programming, music, and language study all require a particular type of spatial intelligence. Language requires studying patterns of sound, semantics, practical (in the street) use of the language vs official (in the books) use of the language, and many other facets. These have many parallels in computer science!!!

You're a superhero and you didn't even know.

The important part of any interview is understanding the question within the question. Given your experience in the industry, you know that people can be jerks. This company may be looking to avoid such people and has found that asking about their high school experience is key. Another tack is that companies may be looking for athletes. Maybe they want to know if you were a varsity athlete or something. Who knows? It would be interesting to hear back from you after the interview.

I am 41 years old with 12 years of professional programming experience, which qualifies me as a senior developer.

As such you have worked both with jerks and with people who were pleasurable. How can one tell the difference in an interview?

I completed high school 23 years ago, where I studied languages, not computer science.

That is an asset. Those studies make you a better engineer. Talk about them fondly. For me, I am a decent electrician because of my high school studies. I am a software dev, too, but it makes me a well rounded person.

Anything before my 12 years of professional experience is irrelevant to the role with the exception of my software engineering degree that I completed 12 years ago when I was 29

Having that kind of attitude might peg you as being a jerk.

worry this could open the door to ageism

Then don't add anything about timelines into your answers. You don't have to mention beepers or cell phones. If pinned down, you can always say things like, "My parents were old school; they wouldn't let me have a phone." Never mind the fact that no one had a cell phone when you were in high school.

or other inappropriate assumptions.

I think you are taking this too far. I think they will ask you about what kind of clubs you were in, and what kind of friends you had. That sort of thing. Obviously those things are only tangentially relevant but I think it is more of a social aspect thing.

Its possible that this job is not a good fit for you. If that is the case be thankful that it was revealed in the interview and you did not have to go through a few months of pain for everyone involved. By asking these probing questions they are trying to figure out if you are a good fit.

How to handle irrelevant questions about high school during an interview for a software engineering role?

Be calm and be polite because the company may have genuine interest in your language skills, which may apply to their business. For example, these are the situations that may work to your benefits:

1. They may need you talk to some potential customers in foreign countries.
2. They may need you train some workers in foreign countries.
3. They may need you write or proof-read some technical documents about software products in foreign languages.
4. In the future, they may create a new AI product related to foreign languages that you may have learned in the past.

I know that if you have not used a foreign language since high school, chances are good that you probably have forgotten all about it.

However, the company may only want to know if you can remember those languages. If you don't remember anything about what you learned in high school, then simply tell them so politely, and everything will be fine. That won't affect your chance of being hired.

Since you are highly qualified in terms of professional experience, an interviewer asking in-depth questions about things earlier than your software engineering degree is simply incompetent. That's a clear warning sign that this job might not be for you. Job interviews are like dating - they go both ways.

Normally the part of an interview addressing your CV should skip through the early years, studies and early employments fast. Or ignore them entirely.

Instead it should be focusing on past employments that either were particularly interesting since they match what you would be doing at your new job, or otherwise on your most recent employments.

Similarly when leaving references, you'd be expected to ideally give your closest manager in the past couple of jobs as reference and not someone from 20 years back.

With 12 years of experience, even your engineering degree is mostly a curiosity. As opposed to when interviewing someone fresh out of school, when the interviewer does have to dig deeper into what was studied and what courses the candidate took etc, since then there are no professional work merits in the relevant field.

Regardless of candidate experience: what anyone did as a teenager ought to be very uninteresting, similarly to details of what one did during non-software-related jobs. There might perhaps be a few who've taken stray programming classes in high school, but since these will be introductory level stuff, the engineering degree supersedes all of that.

However, on good interviews there's a relaxed atmosphere and a bit of "chit chat" about mostly irrelevant things, which the interviewer could initiate just to make the candidate relax and be themselves. Very formal interviews resulting in very nervous candidates benefit nobody. But none of that is an excuse to ask in-depth questions about such.

An okay "chit chat" question to lighten the mood could be something like "Ah so you went at school x, is it down there by the lake? I hear it's nice there", whereas an unprofessional question in this context would be something like "what math grades did you have in high school" or "why did you study a 3rd language when you could have studied programming?". Because you were a teen, probably...

I'd just answer something vague and polite hoping the interviewer comes to their senses. If they don't, I would perhaps prompt them - "sorry, but why are you asking these questions?". Maybe they have an explanation why, maybe they don't.

In general, you have no obligation to answer all manner of weird stuff just because it's an interview. Bad interviewers tend to get sidetracked with some manner of strange agenda that's not nearly as relevant as they might think - this also includes asking very strange technical questions.

A reasonable answer would be "I left high school 23 years ago, so how do you think is anything at high school in any way related to this job?"