This is bound to be more evidence that you ignore or dismiss but here goes:
'The argument that, in the past, selective education provided poor children with a ladder of opportunity compared with comprehensives today is equally dubious. The percentage of the population deemed working class by the Registrar General 50 years ago - 75 per cent - was three times that of today. So to accurately compare the academic achievement of working-class children today with those in the 1950s, the performance of the poorest third from then, those from unskilled and semi-skilled families, needs to be analysed. In reality, only a very small number went to grammar schools and many who did ended up with no, or few, qualifications.
A 1950s Ministry of Education study found that fewer than 0.3 per cent of pupils leaving with two A-levels were from the unskilled working class. Even among the top grammar school streams, a third from the poorest backgrounds left without an O-level. Many poorer children left even before taking public examinations.'
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