The 50-year-old, who has been a supply teacher for four years, says that he has never known jobs to be so scarce.

Mr Edwards, a former primary head based in Dawlish, Devon, registered with a supply agency in early August but has yet to hear anything - a situation he says would have been inconceivable in previous years. His partner, Liz Sutherland, is also a supply teacher and has had a similar experience. At the start of the last academic year, she was picking up an average of three or four days’ work a week but so far this term has had just one day.

Mr Edwards blames the funding crisis and the flexibility that schools have been given by the workload agreement to use classroom assistants.

“The priority for heads now is to save as much money from their budgets as possible rather than getting an experienced teacher in,” he said.

“I am top of the scale and cost pound;30 an hour, so if they can get a cover supervisor in for pound;7.50 an hour then that is obviously the cheapest option.”

He believes that it is the pupils who will miss out, as he says that a good supply teacher can help to reinvigorate a class in much the same way as a visiting author.

“I know how to switch kids on quickly, what works and what will motivate them and get them into a learning state because I have been a teacher for so long,” he said.

But schools may never benefit from his experience again. Tired of waiting for the phone to ring, Mr Edwards has applied for a job as a support worker for adults with learning difficulties.