The idea of somehow finding an extra 47,000 secondary school teachers by 2024 sounds like mission impossible. So is it now time to start thinking the unthinkable - planning for a world in which teacher shortages are the new normal?

It is already possible to discern the outline of a potential future in which fewer teachers per pupil are employed, with options that may be considered anathema today becoming a necessity tomorrow. Some, such as harnessing education technology, could transform the profession as we know it and may be difficult to digest. Are we really ready for teaching without teachers?

Other options, such as increasing class sizes or implementing ways of making it easier to become a teacher, appear more straightforward. “If you don’t have enough teachers, you are going to see class sizes rise,” says Mary Bousted, joint general secretary of the NEU teaching union. John Howson, a teaching recruitment expert and visiting professor at Oxford Brookes University, agrees that “we’re likely to see a continued deterioration” in pupil-teacher ratios.

On the one hand, the government may feel able to let classes balloon because of research evidence casting doubt on whether class size is an important factor in determining pupil outcomes. John Hattie, the New Zealand academic famous for conducting a huge meta-analysis of educational research, has long poured scorn on the obsession with class size.

And the Education Endowment Foundation (EEF) says that, based on existing research, it’s “very hard to achieve improvements [in teaching outcomes] from modest class-size reductions above 20, for example, from 30 to 25”, with clear effects only evident where class sizes are reduced substantially to, say, 15 pupils.

Nevertheless, parents, teachers and voters care about class sizes, and Howson thinks they could be increased, but within limits.

“We’ve seen pupil-teacher ratios deteriorate over the past couple of years, but they are still far better than they were at the start of the millennium,” he says.

“The government may well feel that it can allow them to continue to deteriorate, at least back to what they were under the first years of the Labour government.”

Another option open to the government would be to lower its standard on who it deems good enough to teach. The Department for Education is already beginning to go down this road. It has stressed to teacher-training providers that they must recruit not on the basis of suitability to teach, but on suitability to train to teach. It has told training providers that it will be checking to ensure they are not rejecting suitable candidates.

The government has also announced that candidates will be able to take unlimited resits of the professional-skills test, which must be passed before entering training.

‘Betrayal’ of a generation

Howson says we are undergoing the fourth great teacher recruitment crisis he has observed. What usually tends to happen, he says, “is that a greater percentage of people who apply for teacher training are accepted” onto courses.

But for Geoff Barton, general secretary of the Association of School and College Leaders, any “lowering of expectations or standards” would be a “betrayal of the next generation”. It could even put people off and make the recruitment situation worse if teaching were not regarded as an elite profession.

There are other things that the government might consider doing, too. With recruitment pressure most severe at secondary level, Howson suggests the DfE could look to do something “innovative” with primary teachers. For example, it could “release” some primary teachers to teach students in Year 7 and help with the transition to secondary.

If the English education system weren’t able to grow its own teachers in sufficient numbers, Howson says the DfE could go “shopping around the world”. But this would be easier said than done.

“Our problem is that the rest of the world, particularly in terms of the growth of the international schools, is coming shopping in Britain,” he says.

This point resonates with Arwel Jones, the headteacher of Brentside High School in London. “My young staff, if they want to buy a house, haven’t got a hope at all,” he says. “They’ll look at a job overseas and think: ‘I’ve just got this top job [available] in Abu Dhabi, it’s a lot of money, it’s tax-free.’ Of course, those people are lost for a short while, if not forever, because they get used to the lifestyle and so on.”

With the UK about to leave the European Union, now does not feel like a promising time to seek to increase the number of international teachers working in English schools. “Once we come out of the EU, we will start to lose EU teachers, particularly teachers from Spain, who have been quite significant [in number] over the last couple of years,” says Howson.

The idea of using computers to make us less reliant on teachers might feel even more difficult to achieve. But such technology already exists and is being put into practice in other countries. Henry Warren, an educational technology consultant, points to parts of the developing world in which stark shortages of skilled teachers are driving new methods of schooling that are less teacher-centric.

Bridge International Academies, a US for-profit company, is the best known. Its model has teachers delivering heavily scripted lessons from electronic tablets. Bridge has clashed with teaching unions over compliance with educational standards, but insists these teaching “guides” can “support and empower teachers; [they are] a complement, not an alternative”. Two years ago, Lord Nash, then a DfE minister, met Bridge to discuss its low-cost model of education, although the company says it remains focused on the developing world.

Paranoid about androids?

Tech entrepreneurs are already preparing for teaching without teachers. The $15 million (£10.7m) Global Learning Xprize competition encourages teams to produce software that would “enable children in developing countries to teach themselves basic reading, writing and arithmetic within 15 months”. Onebillion, a British team, is one of five groups that has already received $1m for being shortlisted.

Blended learning is another approach that is often associated with certain charter schools in America - the equivalent of England’s free schools. It sees some pupils in a class taught by software packages that can adapt to their learning, while a teacher is freed up to work with specific groups.

It is a method that Ark - an academy chain highly praised by ministers - intended to use at Pioneer Academy, a new free school in Barnet, North London. Back in 2014, Ark hoped this approach would “improve cost efficiency through both staffing and school-design efficiencies”, but by last year, it was saying the business case “would definitely not be to save money”. Now, Ark says, Pioneer will be a much more traditional school when it finally opens in September 2019.

For Warren, it is just a matter of time before the English school system wakes up to the reality that it will not hit its teacher recruitment targets. At that point, he says, “necessity will be the mother of invention”.

“You have to take some lessons from what Bridge does, and say ‘can we take lesser-trained people and use them effectively?’ And then it comes down to that big conversation about what does technology do better than humans, and what [interactions] do we have to have with humans?” says Warren.

“I suspect what you are going to end up with is teachers taking a much more emotional role and leaving the content delivery to the computers. You can foresee a situation where you have someone who is effectively providing pastoral care. I don’t mean crowd control - I mean proper pastoral care.”

He says these people would not necessarily be subject specialists, but individuals who “have the tools to answer those questions”.

“We can train these people much, much faster because a lot of the skills and attributes you need to do that, they are much more common than the multitude of skills and attributes you need to be a teacher in today’s world,” says Warren. “It’s basically good parenting. If you are a good parent, you would probably make a good pastoral carer, or whatever you want to call it.”

In England, the government is a keen supporter of the use of high-quality standardised teaching material. It is something schools minister Nick Gibb, a keen traditionalist, champions; last year’s Conservative manifesto promised a curriculum fund to encourage leading cultural and scientific institutions to produce “knowledge-rich materials for our schools”. Down the line, could such uniform, standardised texts lend themselves to standardised online learning or scripted lessons, thereby making it easier to cope with a shortage of teachers?

John Blake, head of education and social reform at the right-leaning Policy Exchange thinktank, has said it’s a common sight to go into a school and see “teachers one, two and three in neighbouring classrooms planning identical or near-identical lessons”.

He thinks the workload crisis is already encouraging schools to cut out this duplication through the creation of shared resources. “We have to recognise that it is unhealthy for teachers to believe that they should only be delivering things that they have planned and prepared and designed fully themselves,” he told Tes last year. “That generates a workload culture that is fundamentally unsustainable.”

Don’t flip the script

Because of this mix of factors, Blake already thinks that scripts will become an increasingly important part of the teaching landscape in future years. But could that change also make it easier to go without teachers, or at least what we understand to be teachers, altogether?

“What I would not want to happen is for the current round of educational reforms to be seen as a precursor to, or designed to achieve, a reduction in the teacher workforce. I don’t think that’s the case,” says Blake.

But although he is no ed-tech evangelist, he does see a role for technology in a future with fewer teachers. “You can conceptualise a computer doing certain types of factual recall tasks,” he says, “and perhaps if artificial intelligence gets better at doing some of the marking for longer written pieces, possibly, but all of this is augmentative and does not replace teachers. I think there are all sort of things ed-tech might usefully do, maybe in terms of home learning, and augmenting and supporting the teacher in their work, but I don’t see it as offering a replacement for it.”

If a shortage of teachers forced schools to make greater use of technology, what would be the effect on budgets and, crucially, the education that pupils receive? The EEF, funded by the government to assess what works educationally in the classroom, has already evaluated technology that could replace at least some of teachers’ current jobs. And the results, it says, have been positive.

The foundation looked at Accelerated Reader internet-based software that assesses pupils’ reading ages for teachers, and suggests books that match pupils’ needs and interests. The EEF gave it a “promising project” rating.

EEF chief executive Sir Kevan Collins says that “when the technology is working and the evidence is strong or promising, for example, with the use of Accelerated Reader, it’s very, very efficient because you are just using the software and it’s relatively cheap”. But he is sceptical about the possibility of ed-tech filling the gap left by teacher shortages - “something that seems intuitive and logical, but we have not seen that actually manifest yet”.

Collins then sounds a note of warning: “What we have found to date is that [ed-tech] doesn’t stand alone and you have to supplement it with teachers. Potentially, there are efficiencies, but to think that you can use it to make classes much bigger and reduce the number of teachers - we just don’t have that evidence.”