I’ve been overworked as a teacher too. If schools gave us the right support, we’d survive a lot longer than five years

Do teachers work too hard? Yes, they clearly do, as evidenced by the fact that 40 per cent of them can’t see themselves surviving another five years in the classroom – thanks to the pressure they feel under.

Yet my own experience is a bit different. I became a trainee teacher in September 2017 after three decades as a Financial Times journalist. I have also encouraged 120 older professionals to become teachers through Now Teach, a charity I co-founded in 2016.

A few weeks ago, I surveyed all of them about the best and worst thing about teaching. Even though most of them are knackered by their change in career, only a few specifically mentioned workload as the thing that was getting them down.

Most are not strangers to hard work. Some have spent careers in famously workaholic roles in banking and the law and consultancy, compared to which the long hours in teaching look less bad. In my new job I usually do a 10-hour day, which is long but not unmanageably so, especially given the 13 weeks’ holiday.

What is different is the intensity of the work. Every hour in a school is about twice as exhausting as any hour I used to spend as a journalist. Even in stressful office jobs, there is time to do some internet shopping. Teaching is so full on that there isn’t even time to go to the loo.

Not only does it involve live multitasking in front of volatile teenagers, it is also emotionally draining. You are in loco parentis to 32 children at a time. Even when they aren’t under your nose, you are on the phone to their parents discussing undone homework and other misdemeanours.

So yes, I’m tired. But no, I don’t plan to leave the profession in five years – I hope to be a teacher into my seventies. A big part of this is that I work part time, but also because my ability to manage a heavy workload has gotten better with age.

When I am too tired to be effective, I simply pack up and go home. I never feel bad about it, I think I have done my best and that’s enough. It may be easier for me than the young teachers because I’m more confident and because I’m not trying to climb the ladder and impress my bosses in quite the same way.

Teaching is always going to be more tiring than most other jobs – and there is nothing wrong with that. When things are going well, I feel I get back in pleasure the same amount of energy as I give out.

What surprises me, given the numbers of burnt-out young people leaving the profession, is that most schools seem so happy to make their already exhausted teachers do things that are a poor use of their time.

Workload varies from school to school, and some take better care of their staff than others. My school protects me from constant emails from parents, for which I am grateful.

I’ve worked in another school where there was almost no marking – you would mark four or five books to spot common mistakes and go through those in class.

Equally, schools could rethink the data-entry craze – much of it pointless and all of it boring.

Most importantly, they should collectively do something about lesson planning. At any given moment, thousands of teachers all over the country are planning their own lessons on identical parts of the curriculum – amounting to the biggest case of reinventing the wheel I’ve ever come across.

Schools do little to lighten teacher workloads because they have more immediate things to worry about. Ofsted could help concentrate their minds by rating schools on staff retention, or mark them down for cracking the whip too hard.

While the headline of this latest survey is about workload, I suspect there is something else going on too. After three decades writing about the workplace, I know that people are more likely to put up with long hours when they are feeling generally valued at work.

Some schools are trying to do something about this by focusing on “wellbeing” and yoga for teachers. I have nothing against yoga, but it isn’t the answer.

Fortunately, there is an answer to demoralised teachers and it is free and easy and takes almost no time.

Once school leaders have satisfied themselves that their teachers’ precious time is all spent on teaching, they should spend much more time wandering around the school and congratulating their hardworking staff on the terrific job that they are doing.