Political conference season has come and gone, and while there was plenty to digest, what struck me most was what was not mentioned.

Because, for all the noise around the Advanced British Standard and practical maths, there appeared to be not a glimmer of discussion about the need to dismantle the current school selection system that sees thousands of children funnelled into grammar schools while many thousands more are not.

Maybe it isn’t a priority in a post-Covid world where disadvantage gaps are rising and schools’ building issues are widespread.

But as a long-standing leader in high schools, a headteacher many times over, an executive principal and now chief executive of a trust with secondary moderns across Kent, I feel it’s time for a proper debate about the persistence of grammar schools.

Reinforcing the status quo

This view is driven, in part, by the fact that grammar schools are prevalent across Kent. In living rooms in Canterbury, Maidstone and Ashford, the view that such schools drive social mobility still holds strong.

It is a view I find puzzling, not least because the perspective from the schools I lead looks entirely different: grammar schools are seen to reinforce the status quo and, with very few exceptions, merely reflect the quality of their intake.

For example, as identified by the BBC earlier this year, grammar schools take only small proportions of students entitled to free school meals or those identified with special educational needs. 

In fact, as Sutton Trust research shows, grammar schools take nearly three times as many students who are privately educated as students from less affluent families.

Furthermore, research by Stephen Gorard and Nadia Siddiqui has shown how the “clustering” of children from lower socioeconomic backgrounds has pernicious effects on non-selective schools.

The effects of clustering

With more than two out of every five students in our academy trust in receipt of free school meals, I see the impact of this clustering every day.

These effects include more demands on teachers, poorer behaviour and less civic participation. What’s more, when secondary moderns are denied the supply of higher-achieving children, there is a negative impact on students’ sense of justice and self-esteem. 

Regardless of this lived reality on the ground, the grammar school advocates argue that if a small number of students from poorer backgrounds gain entrance to our great universities it is worth the negative cost to everyone else.

But recent research from Binwei Lu, at Durham University, demonstrably proves that the most able students are better off attending non-selective comprehensive schools because they are just as likely to receive the highest grades - and in some cases more so.

‘Noisy’ data

Other advocates argue that grammar schools score highly in the government’s Progress 8 measure. But research by FFT Education Datalab shows this score “overstates grammar school performance while understating secondary modern performance”.

This is because a key stage 2 test score is quite a “noisy” measure of a child’s educational attainment at age 11. It is not highly correlated with 11-plus results.

Put simply, not all children who pass the 11-plus do their best in key stage 2 tests, mainly because of the significant coaching pupils receive for the 11-plus but also because parents who have already secured a grammar place for their children are not bothered about KS2 tests.

Grammar school advocates argue that children who attend do better in the long run and research does seem to bear this out.

But what the research also shows is that, in areas with grammar schools, the selective system lowers earnings for those at the bottom and raises them at the top.

So, while this might benefit a select few poorer students who attended grammar schools, the net effect is still a pernicious one.

Class ceiling

Consequently, there is not only an immediate negative effect on poorer students in areas with selective education but a longer-term effect that entrenches social immobility too.

This winner-takes-all approach seems curious when administrations are keen to talk about levelling up and creating opportunities for all.

I recognise that there is probably little public and political appetite for more structural reform but surely we cannot continue to support a system where educational opportunities are hoarded for the better off?

Nor is it right that some parts of the country, for historically analogous reasons, have a glass ceiling for students from poorer backgrounds who already face significant headwinds in any case.

Nationally, selection may not be the most pressing issue but, to the communities I serve, it is a constant reminder of the very British notion that your life chances are still determined by what your parents do.

If Keir Starmer’s Labour Party is serious about smashing the class ceiling, then what better way to prove it than to seize this opportunity and end selection once and for all.

Seamus Murphy is chief executive of the Turner Schools multi-academy trust in Kent