She has devoted entire weeks to filling the 22 vacancies that confronted her at the start of the year, only to be frustrated by tiny numbers of applicants, poor candidates and other schools “poaching” her recruits.

And, with the start of the new academic year fast approaching, the only lifeline will be an erratic and expensive stream of supply teachers to cover the two PE, two English, one science and one special needs posts that remain vacant at George Green’s comprehensive on the Isle of Dogs in East London.

The school is in a deprived area and many of her 1,200 pupils come from broken homes. The trauma of having a constant turnover of teachers each week is the last thing they need.

“For many of our youngsters, the only real security they have is coming to school,” said Mrs Frederick. “But with a new face in front of them every week, we cannot provide even that.”

Even when she has managed to appoint permanent staff, she is aware of the danger that they may be lured away by better offers elsewhere or find the capital’s high living costs more than they can stomach.

“I had offered posts to two science teachers but they were offered more money at their own schools and then dropped out.

“I also had an English teacher with two responsibility points but she was unable to find suitable and affordable housing and she dropped out too.

“Increasingly, it seems that teachers carry on applying for jobs even when they have a post in the hope of bettering that (their original) offer.”

But Mrs Frederick is determined not to resort to salary bribes, nor will she appoint anyone she is not fully happy with.

“Instead of paying recruitment and retention points we run a management programme and offer staff the chance to earn responsibility points quickly.

“I will also not appoint anyone until I have seen them teaching. Times may be hard but our pupils deserve the best and I refuse to compromise.”