Pushing at a closed door
According to the teen music magazine I confiscated from a pupil who wasn't fully engaged by my lesson on glaciated landscapes, more than 70 per cent of Britain's highest-selling recording artists and young celebrities have received the benefits of a private education. This is a staggering increase, the magazine tells us, from a figure of about 1 per cent just two decades ago.
There is a strikingly similar trend in the acting world where more stars than ever before are from privileged backgrounds and independent schools.
More often than not, top performers in popular sports also attended private schools with their excellent facilities and after-school clubs. Even football, once the preserve of street kids with natural talent, is now increasingly dominated by those who have enjoyed carefully nurtured, well-planned and expensive training programmes at clubs or elitist independent schools.
Fee-paying schools already have a fine record in helping their pupils to enter lucrative professions such as medicine and law, but now popular vocations that don't demand academic excellence, including music, acting and sports, are also being "colonised" by children from higher-income families - or those on scholarship places.
It is a trend that means the traditional avenues of escape from an unglamorous, low-income existence are being closed off for the less affluent. Doors are being shut. The drive for greater social mobility has stalled and, many would argue, is probably reversing.
Take the example of Ramsay MacDonald. This illegitimate son of poor farmworkers in Lossiemouth benefited from a sound Scottish education, became a teacher himself and then entered the world of politics, serving as prime minister three times during the first half of the 20th century.
Today, it feels as though an elite private-school education is a prerequisite for Britain's top job.
So the key question is this: do talented pupils from poorer families have the same opportunities to make use of their special abilities as pupils from richer families?
In my opinion, they most certainly don't. The deck is undoubtedly stacked in favour of the affluent and the connected, which is why, as so many critics point out, Britain continues to be ruled and represented by an elite of like-minded people from the same middle-class backgrounds.
Most state schools do their best to help pupils to make the most of their lives but resources are limited and nowhere near sufficient to match the brilliance of private schools in opening doors.
This means, I believe, that we are failing to fully develop our human talent and that the strategies being used to try to reduce inequality are not showing any signs of tangible progress. This is storing up problems for the future and the sooner we endeavour to do something about it, the better.
John Greenlees is a secondary school teacher in Scotland