Sarah Cassidy cited Sutton Trust research in an Independent debate on grammar schools.

Research has repeatedly concluded that grammar schools do not boost social mobility. Advocates cite the bright working-class pupils of the 1950s who went on to careers that would previously not have been open to them.

……

A social divide is still seen in today’s remaining 164 grammar schools. A study by the Sutton Trust education charity in 2013 noted that less than 3 per cent of entrants to grammar schools were entitled to free school meals; almost 13 per cent came from fee-paying prep schools.

The same study found that bright children from poor backgrounds were less likely to win a grammar school place than children from wealthier homes who achieved the same level in their SATs tests in the last year of primary school.

Read the full piece here