I know exactly what it feels like to want to attend a grammar school. I decided early on that I did not want to attend the feeder secondary school in my town. I had experienced so much bullying already about a sexuality I did not yet know I had. An out of county grammar school – my native Bedfordshire had long abolished the system but neighbouring Buckinghamshire had not – gave me something to focus on, and a way that avoid both the bullies and the issue they concentrated on. It was an alibi that did not require much explanation.

It was easy to convince my single parent mother who had high ambitions for her first born and believed I could do anything I set my mind to. So the decision was made. Aylesbury grammar was my destination of choice.

We borrowed 11-plus practice books from our “posh friends” whose parents had moved two years previously to be in the catchment for another Buckinghamshire grammar, Dr Challoner’s. I spent what felt like huge amounts of time practising verbal reasoning tests. It is fair to say I was terrible at them. They were unlike anything I had ever seen before, and while I had some challenges in English classes in particular, I had until this point not found a test I could not ace. So I practiced more and more, took advice, and practiced again. I did not have private tuition like others I know – it just was not a option for a family on benefits. Anyway, the test came and went and then the nervous trepidation filled the void that was once practicing for the damn test!

Finally the letter arrived. I fell short by just a handful of points. I had failed.

This was a new feeling for me. Having found verbal reasoning so alien I was actually more prepared than I suggest. I brushed myself down and threw myself into dance club and the school play – hide in plain sight or something like that!

I did not think about the missed opportunity much. My best friend had got in so I heard the occasional stories on the few opportunities there was to catch up. In the end I went to secondary school on the other side of town – a good three mile walk each day – and never considered what might have been. Three years later I got a letter from Aylesbury Grammar offering me at a place at the sixth form. “No thanks” was my almost instant reply.

What unfolded was the realisation my year group was full of people who like me had just missed out but in reverse had crossed the county border to avoid the secondary modern they had been assigned in Buckinghamshire. I had never considered it might be a two-way street. My eyes were opened to what might have been.

This was all about the time I started getting political. A Labour government had not long been elected and they were challenging homophobia in society – trying to repeal section 28 – and investing heavily in schools and improving education. I remember listening to Tony Blair make an education speech and being enthralled. I worked alongside my sixth form studies in a network learning community – one of Labour formative ideas to improve standards – and realised why I am Labour: the belief that the poorest kids should get the best education.

Kids and parents are right to want their kids to go to the best school available to them. I would never criticise a parent for the choices they make. They have to do what is best. The child does not get a second chance at a good education.

It is therefore incumbent on those on the left (and those of us who believe in comprehensive education) to ensure that kids – and their parents – have great schools to choose from. Glib commitments of “every school’s a good school” are meaningless and suggest uniformity is of the upmost importance. Worse, that equally poor is acceptable. You have to have an active school improvement plan, be prepared to replace failing leaderships, recruit from a diversity of teaching disciplines – likely to include Teach First or similar – and a plan for parents if the options available at a given point are not up to scratch.

Labour in office set about transforming schools. The Blair/Andrew Adonis city academy programme ambitiously sought to renew the comprehensive principle and gave expression to what head-teacher Ros McMullen calls a “poor preferred” policy – where schools falling behind while serving working-class communities get prioritised for new investment and a service overhaul and leapfrog their neighbouring schools.

For all their faults Michael Gove and Nicky Morgan at least focused their attention of improving comprehensive schools. Theresa May’s 1950s-style policy for more grammar schools – in the face of all evidence – will set Britain back. Politically it will ruin the Tory reputation on education. It will do little for the social mobility of those who attend and have only negative impacts for those who do not.

In our favour, Tory ideas of more grammar schools are met with indifference from voters in general and parents in particular. This is in no small part because of Labour’s academy programme. Even John McDonnell agrees. The vast improvement in state schools, especially for those in areas of historic deprivation and underachievement, has reduced the demand of middle-class parents across the country for grammar schools or private providers. In re-discovering our reforming zeal Labour can leave the Tories standing on grammar schools, stop the proposals in parliament (because some Tories will vote with us) and stand up for every child in giving expression to the Labour value – no child left behind.

Next week the government consultation closes. Labour can show a united front on the error of their ways. To this end Angela Rayner, Lucy Powell and Estelle Morris lead the pack of speakers at the Progress rally against grammar schools. It is open to all Labour members and those beyond our party that oppose these regressive proposals.

Richard Angell is director of Progress. Join the Progress rally against grammar on Monday, 12 December, 7-8.30pm, Committee Room 15, Houses of Parliament. Speakers include Angela Rayner, Lucy Powell, Peter Kyle, Estelle Morris, Catherine McKinnell, Stephen Twigg and Wes Streeting.