Image copyright iStock Image caption The Kent entrance system is like playing with loaded dice, say the report authors

The odds are loaded against children from disadvantaged backgrounds who apply for grammar schools in Kent, suggests a study.

Entrance tests for the county's grammars "understate the true academic abilities" of poorer children, says the Education Datalab report.

The "heavily" selective county will be a useful case study if grammars are rolled out nationally, says the study.

Kent County Council said it was working to boost social mobility in grammars.

Ministers have announced plans for a new generation of grammar schools in England by 2020.

"We want to see more children from disadvantaged families get into grammars," said Education Secretary Justine Greening in a speech last month.

But Education Datalab's analysis suggests the selection process in Kent does not always identify "the most academically capable children".

The report uses data for children who sat the 11-plus in 2015, obtained under Freedom of Information law by Kent Education Network, which opposes selective education.

The figures show 12% of free school meals pupils passed the test in 2015, compared with 30% of their better off classmates.

Tough reasoning

Kent primary schools are "explicitly asked not to prepare their pupils" for the 11-plus tests, say the authors, and this favours children whose parents can pay for private schools or tutoring.

Free school meals pupils fare worst in the verbal and spatial reasoning paper, which is not part of the national curriculum, say the authors.

The study identifies a difference between the scores of pupils on free school meals and those of their classmates of:

7.7 points in the reasoning paper

6.8 points in maths

3.9 points in English.

"With only around one in four children getting into grammar school, and with the odds stacked against those from poorer backgrounds, securing access to a grammar school in Kent is like rolling a loaded dice," said lead author Rebecca Allen.

The authors say the attainment gap is greater in the Kent 11-plus than in the national assessment tests taken by all state school pupils at the end of primary school.

Their recommendations include:

allowing state primary schools in Kent to practise the reasoning test with pupils

giving pupils on free school meals extra marks, particularly on the reasoning test

They also suggest simplifying the entrance system by removing head teacher panels that can decide to admit children who have narrowly failed the test.

And they urge Kent County Council to admit the tests sometimes "misclassify" children, adding that, along with their children's marks, parents should be told the odds these scores might be wrong.

This is particularly crucial for children on the borderline where gaining or losing a single mark could determine whether they go to grammar school or not, say the authors.

Image caption Grammars should be opened up to ordinary families, say ministers

Patrick Leeson, Kent County Council's corporate director for education, said the council had begun to implement a series of recommendations in a report last June and there had already been a small increase in the number of children from low-income families gaining grammar places.

"But we recognise that there is still more to be done," he said.

"We are working to improve education for all children in Kent, which includes ensuring that students from any background can attend grammar schools and benefit from a selective education if that is the right choice for them."

Jim Skinner, chief executive of the Grammar School Heads' Association, said the organisation was "fully supportive of primary schools doing preparation with pupils, which is proven to boost the pass rate among children from poorer families".

But he said he found other recommendations, in particular the removal of head teacher panels "most puzzling" and suggested the report authors were "looking to make a case against selection".