Graduate admission for mature Computer Science school teacher The mother of my friend is a senior computer science high school teacher in India. She did a masters in Information Technology around 25 years ago in India and wants to restart her education. She want's to pursue a (preferably funded) PhD in CS from a decent university in North America or Europe.

Would her 20 years long experience as a CS teacher be of help ? 

Since her Bachelors is not in CS (in another STEM field) would this adversely impact her chances ? 

And finally how much will her age (40s) impact her application ?
I would guess that in the US, if she is willing to start a program that will take 5 to 7 years, she would have a chance for admission. It is an unusual case, but she has learned much, I think, of what a CS undergrad learns here. There will probably be a few missing pieces, such as theory, but that might be made up with the required coursework that is normally done. I'll have to guess that the IT masters won't be of a lot of use, unless it is quite different from what happens here. And things have changed a lot in IT in 25 years. So the length of a doctoral program would depend a lot on what knowledge she can demonstrate. 

Age shouldn't be an issue. Funding might be, but she is also probably a great candidate to be a TA for the beginning courses. The biggest problem might be visa and coronavirus issues, of course. 

But she can only know if she makes some applications and, perhaps, explores her options with a professor or two.