I am at a loss here. Not because I’m short of material, but because memory after memory floods over me and I fear I can’t do anyone justice. I’ve served in six remarkably varied schools, from the most privileged to the least advantaged, and I have a long list of pupils I’ll never forget.

There was the senior group of inner-city youngsters we took to Stratford for Shakespeare. They put their peers from other more advantaged schools to shame with their dress, behaviour and maturity. I remember them with pride as they grabbed the dishcloths and brushes in the youth hostel, determined to show the others how it should be done.

Then there were Peter, Robert and William, and others like them. They came to secondary terrified, like rabbits in the headlights. Didn’t think they’d last a week, far less five years. But they did. And the immeasurable bravery and commitment they showed in the midst of exceptional difficulty stands out. It was the small steps, each a victory in its own right. They would appear like a shadow at your shoulder, initially for help, reassurance and comfort; latterly for praise and the sharing of family news and their own progress. Statistics cannot easily measure that success.

But there is a special place in my heart for the many foreign students who come our way. There was Ji, who took all before him, and still does. Alia, who was less than enamoured with my arrival as head, yet who, on her departure a few years later, wrote me one of the most moving letters I’ve ever received. And, finally, Maryam, whose parents had to return to Iran.

She astounded doctors with her biology research in her sixth year, and fought to gain her medical degree, alone, in the UK. It was a privilege to be invited, with my deputy head, to be guests at her graduation and, in place of mum and dad, watch her take her Hippocratic oath.

They all had one thing in common: against the odds, they rose above the challenges and left their mark on their educators. And wherever they are, I hope the successes they enjoyed then are bringing them happiness today.

Ken Cunningham is head of Hillhead high school, Glasgow. Do you have special memories of unforgettable pupils? Write to Sarah Bayliss at the address on page 3 or email: sarah.bayliss@tes.co.uk