A body representing head teachers in England, Wales and Northern Ireland have called for more early years investment instead of opening more grammar schools, the Observer reports.

The National Association of Headteachers (NAHT) submitted an unpublished document to the Department for Education attacking Prime Minister Theresa May’s plans for more grammar schools, stating that the policy will hinder social mobility.

The document states that the damage to children’s life chances is done in the early years of life. It notes that the gap between children from low-income households and their peers in passing five or more GCSEs, including in English and maths, grows to 60% by the time pupils reach the last year of primary school.

When children who have received high-quality early-years education start school, they are up to eight months ahead of their peers in literacy and language skills, the submission goes on to say.

New analysis from the House of Commons also reveals that four of the five areas where disadvantaged children perform worst, compared with their wealthier peers, are in areas where secondary education is fully or partially selective.

Declining to comment directly on the submission itself, the head of the NAHT, Russell Hobby, said:

“The evidence does not support the expansion of grammar schools: they do not contribute to social mobility and will distract attention from the things that really matter.

Instead of this divisive and risky reform, we need a firm focus on the most pressing issues within education: getting great teachers for the pupils who need them most, supported by confident leaders and with access to an evidence base of what works.”

The government’s controversial policy shows no signs of being reformed, as various stakeholders in Parliament and wider society reiterate their views on the issue of grammar schools. Former shadow education secretary Lucy Powell commented:

“Ministers are failing to heed the warning from head teachers that it is a deep pool of excellent teachers and enough resources that will help them make a difference and narrow the education divide, rather than fetishising grammar schools as a silver bullet to tackle the social mobility crisis.

There is a growing alliance in parliament against the expansion of selective education. If the prime minister continues to ignore the evidence of what works in education, she will see her grammar school plans blocked.”