That’s the conclusion of the FT’s Chris Cook in a piece that looks at how educational results vary between selective and non-selective areas in England:
Poor children do dramatically worse in selective areas.
There is an idea out there in the ether that grammar schools are better for propelling poor children to the very top of the tree. But, again, that is not true. Poor children are less likely to score very highly at GCSE in grammar areas than the rest…
This is all driven by the process of selection itself: poor children are more likely to be behind at the age of 11, and less likely to get places in grammars.
Grammar schools are a part of many people’s identities: having won admission to a selective state school plays an important role in the story of their life, especially if they came from a less privileged family. But, as a way to raise standards or to close the gaps between rich and poor, it is hard to find evidence that they are effective.
You can see all his evidence about selective state education here (free registration may be required).