Mark Morrin is Principal Research Consultant at Respublica.  Phillip Blond is the Director of Respublica.

There are seemingly few topics in domestic politics as headline-grabbing or divisive as grammar schools. ResPublica’s review of educational attainment in Knowsley, Merseyside, makes over 30 recommendations to help improve performance in the borough. The suggestions on grammar schools constitute just one of the recommendations we make – to whit that government should ensure any future grammar schools target the most disadvantaged areas where there are no existing schools rated good or outstanding by Ofsted. Judging by some of the local reaction, we might just as well have suggested the good people of Knowsley stand on the Kop and extol the virtues of Manchester United.

Knowsley is currently the second most deprived authority in England and, according to the 2011 census, one of the least culturally diverse; over 95 per cent of the resident population are White British – the demographic doing least well in our current education system. Its secondary schools are currently the lowest performing in the country, and have been for some time. They have tried comprehensives, they have built schools for the future, they have converted to academies. And so far nothing has worked. Large numbers of the most academically capable pupils – the top 20 per cent – continue to transfer out of the borough for their secondary education.

The brutal truth is that there is already selection in places like Knowsley. Those that can select academic education out of the borough, and those that can’t are abandoned to their local fate – a situation made worse by the closure of all sixth forms in the borough.  So no school will be offering A levels next year.

We completely accept that grammars are not the only way to achieve success – but what is clearly needed is for at least one school in Knowsley to be an academic beacon and an outstanding academic school, such that those who currently leave the borough are persuaded to remain.

It seems asinine to ignore the possibility that new legislation allowing for a grammar school to emerge in a place like Knowsley could provide the kind of ‘magnet’ which would help reverse the current flow of pupils out of the borough. Grammar schools could thus act as vital cultural enablers to turn around and transform parts of the country that have been left behind. They could be a driver for economic growth, stimulating house prices and attracting middle class families. Grammar schools are popular with many parents, and an existing academy in Knowsley, we believe, may well choose to respond to this opportunity. One of the borough’s academies, Prescot School, has recently reverted to its former name precisely to associate with its proud 500 year history as a grammar school. If it does become a grammar, we humbly suggest that the borough should welcome this rather than oppose it, for it could be the quickest route to what areas like Knowsley most need: an excellent academic school.

There are a number of well rehearsed arguments against grammar schools – that they are elitist; overwhelmingly favour the middle classes, and do nothing to address the widening social mobility gap. But what we do know about grammar schools is that high-achieving children from disadvantaged backgrounds will improve their performance by nearly ten percentage points compared with equivalent children in non-selective schools. The real issue is that too few working-class pupils currently attend grammar schools. In fact, what the evidence tells us is that grammars don’t particularly advantage middle class children, who would succeed just as well in non-selective schools.

The problems in Knowsley are of course multi-faceted: we believe that a grammar school is only part of the possible answer. We at ResPublica have also called for a ‘Team GB’ approach which, in an education setting, would mean following a ‘marginal gains’ strategy with a much greater focus on data and the monitoring of performance in schools against key metrics. Co-ordinated across the borough, this would see improvement interventions targeted at the student, the teacher, the curriculum, the school leadership and management. All these interventions will have benefits for attainment; all must be applied at the same time, and all must be closely monitored for impact and continuous refinement.

We have also called for the introduction of a Northern Teaching Premium to attract quality teachers to the region through incentives which could include: opportunities for teachers to gain a step up on the housing ladder within a commutable distance of their school; financial assistance with student debt; and bursaries for PhD students to teach in secondary schools. ResPublica has previously advocated a ‘Teach Later’ programme for career changers and returners to the north. Interestingly, a recent study by the Centre for High Performance reveals that the most effective head teachers have moved into education after a period of between ten to 15 years successfully working in industry. There is clearly evidence for a targeted policy intervention here.

But if grammar schools are to be part of the solution for places like Knowsley they must genuinely serve the brightest kids from the poorest backgrounds. A new wave of grammar schools should target the most disadvantaged areas, where there are no existing local schools rated Good or Outstanding by Ofsted. They should be in places that have the greatest need for future economic growth. Importantly, any system of selection should identify – based on means – and meet a quota of children (say a minimum of 60 per cent) from poorer backgrounds, before offering places more widely. The challenge would be to establish mechanisms for primary schools to prepare their most able pupils for a ‘tutorproof’ entrance exam, and to raise standards for all children in the process so that the non-selective schools are not left behind and overall performance is improved.

Theresa May is right to identify that selection by house price already exists in our education system. Property prices and gentrification are an integral part of the success of schools in London, where rich and poor live cheek by jowl. Outside of London, the result is largely good schools in prosperous areas and failing schools for the poor. A mixed ecology including comprehensives, grammars, free schools, and academies is needed in our most disadvantaged communities, with scope for different learning methods to meet the different needs and abilities of all children.  We ae not calling for the reintroduction of the grammar/secondary modern divide, but for selection for all children across the ability range so that if a child’s talent lies more in the vocational direction, he or she should have a first rate pathway to achieving that goal. There must therefore, alongside the new grammars, be a new selective pathway for the very best of vocational training, and clearly University Training Colleges have their role to play here. Not all schools should be dedicated to achieving the highest academic standards. But this should not be at the expense of achieving the highest level of excellence in other areas.

The current system has not lifted all pupils equally. In fact, most approaches to help narrow the education gap have resulted in what sociologists, in borrowing a biblical term have called the ‘Matthew Effect’, in which advantage begets further advantage: ‘to them that hath shall more be given’. Introducing grammar schools in places where schools are failing will help all pupils of all ability if, as the Government’s Green Paper recommends, they can ensure support to non-selective schools in their area, and work with feeder primary schools to enable this phase of education to meet the requirements of a selective system. The key to making this iteration of the grammar school work is to avoid the two-tier system of the past and to prevent middle class families from manipulating the system for their own gains – hence our call to initially place grammars in only in the most disadvantaged areas. That grammar schools have been overwhelmingly colonised by the middle classes is not an argument to abandon them as institutions hopelessly lost to privilege, but to recast them such that they can only support and engender working class talent.