Reforms to teacher training over the past few years have radically transformed the way that teachers are recruited and trained. The introduction of school-led teacher training programme School Direct has meant schools are now directly involved in the teacher-training process in a way that was unthinkable a few years ago. This means schools can recruit the teachers they want, choose the university they would like to work with and, crucially, decide on the content of the programme.

Historically, universities had seen teacher training as a good and reliable source of income and, more importantly, they had near total control over the content of their courses.

This level of control and lack of consultation with schools meant that new teachers arrived in schools having been subjected to training that focused on “progressive” theories of education that were of no use in the classroom. The most essential, practical skills, such as behaviour management or how to teach children to read, took second place to ideology and dogma. During my teacher training, we were taught that children who misbehaved were protorevolutionaries against the imperialist, capitalist state. All very interesting, but not much use for getting my class in from the playground without a fight.

Subject knowledge was seen as unnecessary and there was little or no focus on raising standards. When Ruth Miskin devised her synthetic phonics programme at Kobi Nazrul school in Tower Hamlets, she was seen by the education establishment as an eccentric crank simply because she was determined that her pupils, many of whom were from Bangladesh, would leave primary school with the ability to read.

School Direct has given schools and headteachers the power that they always wanted because they know that not a minute can be wasted in the precious few months during which teachers are trained.

The reaction from universities has been interesting - initially, there was a lot of resistance, both because their income was reducing and because they were under scrutiny like never before. The most forward-thinking saw this as an opportunity and have developed strong partnerships with schools that have seen better-designed training programmes; they have also allowed experienced teachers to take master’s degrees or begin to work towards a doctorate. Some of the supposedly most-prestigious universities have not had the humility to engage properly with schools and they have seen their market share fall away.

These reforms have led to the best-trained generation of teachers we have ever had with high-quality recruits beginning their careers well prepared to succeed in the classroom.

Rising demand

Although these reforms have had a marked effect on teacher quality - as headteachers across the country will attest - they have come against a backdrop of an improving economy and spending constraints across the public sector, which have made it difficult to recruit in some subjects, in particular those such as maths, physics and computer science for which demand from pupils has increased enormously. There are 25 per cent more pupils taking the further maths A level now compared with 2011.

We now have more teachers in the profession than ever before and a greater number are trained each year, but it has been hard to keep pace with demographic changes and the hunger for more-academic subjects.

Supply teaching agencies have hungrily seen these shortages as an opportunity to expand their market. Schools now spend well over £1.3 billion of taxpayers’ money on supply cover. But the agencies are not popular. Get a group of heads in a room, ask them about supply agencies and you will hear a long list of complaints.

Schools pay as much as £220 for a day’s supply (even higher for shortage subjects), while the teacher will get as little as £120 gross. The rest goes into the profits of the supply agency. The process for hiring a supply teacher is time-consuming, especially in small primary schools, where the task often falls to the headteacher or hard-pressed office staff at the busiest time of day.

I was once the head of a special school for children with severe emotional and behavioural difficulties, but agencies continued to think that if a teacher or a teaching assistant had worked in any special school, they would be right for me. That meant that we were often sent people who may have been fantastic with children with severe learning difficulties, but who were completely unsuitable for my feisty pupils.

Sometimes, agencies send a really good teacher and the school decides to offer them a permanent job, but the agency then demands a slice of the teacher’s first-year salary. Their starting point is usually 20-30 per cent, but with persuasion they might drop their price. Headteachers in particular hate this practice. They are often not comfortable haggling, (why should they be? It is not why they came into the profession). The whole process usually leaves a bad taste in the mouth.

Increasingly, agencies have inserted themselves between schools and teachers, where they add no value - they just extract more money from schools. One such example is with NQTs. It used to be that schools would go to NQT fairs and find great candidates. Now, agencies have muscled schools out - they go to fairs and get NQTs to register with them, so they can charge a 20 per cent first-year-salary commission to the school. This practice is a disgrace and must end.

Resentment of agencies does not end with schools. Teachers on agency books feel they are promised rates that they never receive; they get sent to schools that are miles from home; they are not told the truth about the state of the school they are going to; and, once the agency has taken its cut, they end up with a paltry wage packet.

I have heard of cases where a supply teacher is sent on taster days to a school, so that the head can assess whether they are suitable but, outrageously, the agency charges a full day rate to the school and the teacher gets nothing for their work.

The whole way teacher supply works must change. There needs to be more transparency, greater fairness for schools and teachers, and much lower commissions.

Technology is the obvious solution and has worked in other industries. Done right, it would mean hundreds of millions more each year of much-needed funding for schools and more money in the pocket of teachers rather than agencies. A win for teachers and a win for children.

The parent company of Tes magazine owns and runs several teacher-supply agencies

Charlie Taylor is executive director of Zen Educate, an alternative to recruitment agencies; he is the former chief executive of the National College of Teaching and Leadership, and ex-headteacher of The Willows, a school for children with complex behavioural issues