He has been a support to management in a period of major changes in the school's direction and, after a 35-year career, he still maintains a love for his subject and an enthusiasm for teaching. Visiting his class always leaves me feeling better.
He is not alone in retiring this session, nor is he unique in bringing value to his daily tasks. But he does contrast with one of the saddest perspectives of teaching, when colleagues who see retirement looming - tantalisingly close but still elusive - can't wait to get out of the profession. How sad to devote a lifetime to developing future generations and feel in some way trapped or imprisoned in their posts.
I visited an inmate in one of Scotland's prisons recently. Now there is a place where "getting out" carries with it a cry of real despair.
Certainly the pressures on us all in schools have changed and most would argue they have intensified. All the major professions will testify to increased pressure, the need to meet deadlines and accountability at every turn. Society expects and demands higher standards. Add to this the ongoing debate about fair recompense for the expertise and training brought to the job. All this is universal: the scenario does not relate solely to teaching.
This year, St Paul's High has been privileged to have four probationer teachers. I heard recently of a headteacher who is unwilling to accept any.
I scratch my head at such vision. Had the same applied when any one of us started, where would we be? Does he know what he is missing?
Not only do probationers develop in their fixed first year - and I sincerely think our four colleagues have - but other things happen too.
Schools become fresher. Principal teachers have a huge developmental role to embrace and their own professionalism is enhanced. Colleagues on a wider front see enthusiasm and high expectations come to work daily. And pupils love new, and generally young, teachers arriving.
From probationers come the future headteachers, directors and policy makers in education, the movers and shakers of the future. How I love to welcome them through the school doors.
Our four young colleagues will leave St Paul's High shortly. Here is a whistle-stop survey of what they have found:You have to be flexible. Coming with rigid and set ideas gets you nowhere.
Changing your opinion is not only allowed, it makes you a better teacher.
Beginning to relax in the classroom makes for improved pupil responses.
Believing that pupils can respond to difficult tasks actually works; they will.
Moving from criticism of pupils' work to praise for their achievements produces magical results.
Becoming aware of pupils' backgrounds was a huge learning experience.
Working with experienced, committed, talented colleagues has been hugely enriching.
Unanimously they identified becoming involved beyond the classroom as an important leap in relating to pupils and in pupils changing attitudes towards them.
In any school function held beyond the working day, I notice the same staff being present. These are the ones who tend to carry their enthusiasm around with them day to day. Pupils are inclined to enjoy being with them, too.
Perhaps they still have whatever it was that attracted them to getting into teaching.
To our retiring principal teacher I wish a long and healthy future. To the probationers I offer the great hope that what they have within them today remains with them throughout their careers.
Rod O'Donnell is headteacher of St Paul's High, Glasgow
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