Grammar schools are an interesting one.
I passed the 11+ in 1980 along with about 9 other children. We five girls went off to much acclaim. Interestingly we didn't know we were taking the 11+. There had been no tutoring and our average C of E primary didn't have languages or anything like that on the curriculum, yet still we passed.
My family have always been genteel poor, making tiny climbs up the ladder from my Nana in service and my Mum finally ending up in secretarial work. I remember a grandmother clock being sold to pay for my exclusive uniform - it cost £200 in 1980 and was considered a worthy sacrifice.
But my background was vastly different to the majority of other pupils who largely came from private schools and whose parents had money, so social exclusion was a bugbear. Add in the weird inverse snobbery at home and while I came away with a decent set of O-levels and was pointed at Oxbridge, I couldn't take the pressure nor fit in.
I'm still poor. Poorer now than I've ever been before because I've put family and caring responsibilities first every time.
My son ended up at the same primary school. In his last year it was revealed to me that his teacher didn't think it was worth him doing the 11+ despite being "bright" - most of his friends had been tutored for it. I had no idea the system had changed. I didn't think to ask. I felt like the world's worst mother. He did sit the exam and missed by about 5 marks. On reflection he would have struggled socially the same as I did. His current career as a landscape gardener is his choice and I'm proud of how hard he works.
So I now think that education should be of a high standard for everyone. The original concept might have been a good idea, but it has been overtaken by the changes in the modern world.
Everything about global society is changing very quickly and we need a better, more equitable approach to pretty much everything.