It's a few years since I left the Civil Service, but there were certainly a number of people - mostly senior officials - who kept a fountain pen specifically for 'writing off' documents - and I suspect that if fountain pens are used at all in schools it will be by senior teachers for much the same purpose. Pupils not so much. Though I learned with a dip pen (actually I have a vague feeling that I may be old enough to have used chalk and a slate for very early writing experience) and still have a supply of both fountain pens and dip pens for calligraphic work (a legacy of art college) I doubt that schools use them much.

I expect that there are a number of people around today who (inspired by Harry Potter) know how to use a quill pen.