So you want to know about the recruitment crisis
Is there really a crisis in teacher recruitment?
Schools minister Nick Gibb admits there is a "challenge" but insists the government is managing it successfully. Many headteachers view the situation as much more serious. Teach First believes the problem is worse than it was in 2002.
What happened in 2002?
Back then, everyone agreed there was a crisis. Severe teacher shortages forced heads and supply agencies to scour the globe to fill the gaps in England's staffrooms. The situation was so extreme that the government decided to allow support staff to take lessons unaccompanied in certain circumstances.
Schools are once again recruiting from abroad, with teachers arriving from Canada, Australia and Ireland. New statistics released this month show that increasing numbers of teachers are being asked to cover subjects outside their area, with fewer maths, English and science lessons taken by teachers who have a post A-level qualification.
So why do ministers insist there is no crisis?
They point to official figures showing that teacher vacancy rates have remained stable at about 1 per cent for the past 15 years.
Does that mean there is no national problem?
Not necessarily. Teacher recruitment expert John Howson, a senior research fellow at the University of Oxford, points out that government statistics no longer compare like with like because they have stopped picking up Christmas vacancies. Despite that, the overall national vacancy rate has doubled to 1.2 per cent since 2010. Professor Howson has described ministers' attempts to deny the problems as "rubbish".
"You have figures going in the wrong direction on the best possible day of the year to collect them," he said this week. "If that is not a warning sign, nothing is."
Which areas of the country are experiencing the worst shortages?
London and the South East are first to be hit this time, as they were before. Housing costs make it harder to attract recruits from other parts of the country.
Do any subjects have particular teacher recruitment problems?
A survey by the Association of School and College Leaders in December 2014 found that two-thirds of respondents had difficulty in recruiting maths teachers and almost half had problems in science and English. Computing and modern languages are also starting to experience issues because changes to the curriculum and accountability measures mean that more pupils are taking the subjects.
Are primary schools experiencing teacher shortages?
Vacancies in primary schools are increasing but recruitment remains strong. However, concern is growing over hiring headteachers in the sector.
What are the reasons for the shortages?
First, a lot more children are coming into schools - by 2021 there will be 900,000 more than there were in 2010. Then there are curriculum and accountability changes, such as the English Baccalaureate, meaning that more teachers are needed in certain subjects. At the same time, the economy has picked up. That makes it harder to attract graduates into teaching, because they have a greater number of career options to choose from. Teach First says the graduate jobs market is more competitive than ever.
Is the bulge of baby-boomer teachers retiring still a problem?
No. That peak has passed.
How long will these shortages continue?
The growth in pupil numbers is set to continue until at least 2023. Meeting the increased demand for teachers largely depends on attracting people into training. But David Laws, then schools minister, told Parliament earlier this year that the number of secondary trainees was falling year on year, from 19,440 in 2010-11 to 12,943 in 2014-15.
For 2016, the National College for Teaching and Leadership has tried to address the shortfall by abolishing the limits on how many teachers can be trained by individual universities and schools. Dr John Cater, vice-chancellor of Edge Hill University, fears that such a free-for-all will worsen the crisis by introducing more instability to the system.
What can be done to solve the problem?
National marketing campaigns can encourage more people to apply for teacher training but there is also the difficulty of keeping teachers in post. Unions say that in order to retain staff, workload issues must be tackled and pay needs to rise.
Professor Howson argues that the current system does not make the best use of the teachers who are available. He says that too many people who have gone into the profession as a second career are limited geographically because of family commitments and cannot find jobs where they need them.