Most staff will be unable to avoid superimposing the first-year faces of six years ago, bright with excitement, necks chafed by the brand new uniform, on to the more mature visages of those about to leave school, with the additional experience of teenage years.
It is perhaps the greatest quality assurance exercise of all, remembering the highs and lows of their school life - the shy pupil who has matured to confidence or the primary high-flyer who never quite made the predicted progress. Inevitably there will be successes and regrets.
Schools and teachers do their best for their pupils but, in the end, are just part of the life experience that sees 12-year-olds progress to their late teens.
This year's leavers' day was particularly poignant, my son being among them. Being year head as well as dad is an interesting experience - seeing school life from the angle of manager and parent at the same time is like a distillation of every point on every page of How Good Is Our School?
Happily, my son's brilliant experience at our school has meant that my acknowledgment of the expertise, commitment and compassion of our staff has been lent added authority by my dual experience as colleague and parent.
For this dad, winning the lottery would be as nothing compared to the peace of mind given by witnessing the progress and development of my son in the care of our staff, teaching and non-teaching, during his time here.
All conscientious teachers hope that their own institution gives every pupil the quality of education they would want for their own children, and I have been in the privileged position of seeing that wish fulfilled.
The crucial nature of the partnership between home and school, of school ethos and the results of simple hard graft by a teaching staff, are a living reality to me, and the feedback from our parents and the wider community tells us that we are getting it right with most of the pupils most of the time. No room for complacency, but certainly the appetite for progress that comes from such encouragement.
On the wall, the Curriculum for Excellence poster catches the sunlight as the last of the sixth year, shirts signed, ties finally removed, head for the buses. And I dare to hope that perhaps that poster might be the ideal epitaph for the class of 2006: successful learners, confident individuals, responsible citizens, effective contributors.