The market works for the sale of sausages: there is a wide range on the supermarket shelf, produced by different companies, offering choice to the consumer on price, quality and flavour. There are several ways in which the market works in education too: a choice of textbooks and equipment suppliers is good for schools; teachers like the opportunity to choose between different awarding bodies; and an element of competition between schools helps to avoid complacency and induce pride in the quality of education provided.

But too often for children, unlike sausages, the market doesn’t work, leaving some young people with a much worse deal than others.

Teacher supply is one area in which the market certainly isn’t working at the moment. Having abdicated much of its responsibility for planning teacher numbers, the government has recognised, in one aspect at least, that the market isn’t working and is to be commended for taking action. Schools in challenging areas and in remote or coastal locations are finding it even tougher than elsewhere to recruit and retain good teachers, and for some schools it is making their job of raising achievement almost impossible. If the government can get the incentives right for both schools and teachers, this represents an appropriate place for government intervention in the market.

Improving teaching and leadership

So the education secretary Nicky Morgan has launched a National Teaching Service (link free to subscribers) - “a new national programme that will get our best teachers and middle leaders into underperforming schools in areas where they are needed most.”

NTS teachers will be employed by these schools for up to three years and “will be expected to improve the quality of teaching and leadership throughout the school,” according to the Ms Morgan.

The pilot starts in the North West in September 2016 and will be rolled out nationally a year later. Applications from schools and teachers close in five weeks’ time, on 11 March.

In the same week that the education secretary made her announcement - rightly mentioning middle leaders as a central part of the NTS - I spoke at the Teaching Leaders graduation in Manchester and, in 2015, 268 high-potential middle leaders from across the country graduated after two rigorous and challenging years of professional development with Teaching Leaders.

Teachers have a lot more freedom than many employees in other sectors to decide what part of the country to work in. Bodies such as Teach First, Future Leaders and Teaching Leaders have therefore made it their mission to increase the supply and improve the development of high-quality leaders in schools across the most challenging areas of England, and I have strongly supported all three of these organisations since their foundation. So has the government.

All three of these organisations focus on leadership as well as classroom practice. Teachers - even good teachers - cannot flourish without good leadership, so there should be more focus throughout a teachers’ career on leadership development. After all, every teacher is a leader and can benefit from building the skills of leadership.

Middle leaders are key

Good teachers are unlikely to flourish in the NTS unless they are well led, so it is the deployment of excellent middle leaders who will support and mentor less experienced NTS teachers in their new context, setting a clear vision and translating it into action, that will bring success to these schools, making the government’s investment worthwhile. Middle leaders are the key to the success of the NTS.

Middle leaders are the engine room of school improvement. It is they who will make the change to pupil outcomes sustainable. NTS teachers cannot take all the lessons themselves; they need to work through others to make schools successful, with the right kind of line management to bring the best out of other staff. Good line managers will help to improve the quality of teaching and the retention of teachers in challenging schools and ensure that disadvantaged pupils receive high-quality teaching.

Both within the NTS and throughout the school system, more thought needs to be given to leadership development and, in particular, the leadership development of those below the senior level - the leaders of the present who will be the senior leaders of the future.

With the loss of leadership focus in the National College for Teaching and Leadership, there is no longer a clear vision across the system of a continuum of leadership development and career progression, which is what middle leaders often say they want. If a clearer path, with training hubs along the way, existed, good teachers would be better motivated during the years between initial qualification and headship preparation. Ambitious young middle leaders need to be able to see where they are on the leadership spectrum and where they could be in five years’ time. NTS may help to reinvigorate and retain our most talented middle leaders, but it needs more than the traditional teacher job market to ensure that they stay in the profession and progress to senior leadership roles in places that can best use their undoubted talent.

John Dunford is chair of Whole Education and was formerly a secondary head, general secretary of the Association of School and College Leaders and national pupil premium champion. He tweets at @johndunford

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