John Atkins clearly recalls the turning point for his school - it was at the height of the teacher recruitment crisis more than two years ago.
"I was looking out of my window one day, thinking how are we going to get this maths teacher? I had made 20 to 30 phone calls, tried all the agencies, tried abroad and sent out emails.
"And then I thought - we have to do something different. If we want to improve teaching and learning, reduce teacher workload and address the teacher shortage, we have to strip everything out and re-invent the school."
So he did. Since then Kemnal technology college, an 11-18 boys'
comprehensive in Bromley, south London, has been transformed.
It has raised its standards through new technology, tackling teacher workload and bringing in innovations including classes of up to 75 students.
The school now finds itself in the spotlight - schools minister David Miliband recently visited. It is one of 103 "leading edge" schools that promote innovation and share good practice with other schools.
In 1990 Kemnal was a failing school with 570 on roll and just 7 per cent of students achieving five Cs or better at GCSE. By 1999 the figure had risen to 29 per cent.
Last year 56 per cent achieved five good grades, well above average, while this year's figure was 50 per cent. For the past two years the school has won a Department for Education and Skills achievement award.
The school now has 1,300 on roll, and gets around 470 applications yearly for 270 places.
It has a challenging intake. Some 60 per cent start in Year 7 with a reading age below what would be expected. A fifth are eligible for free school meals, and 30 per cent are on the special needs register.
A major step has been the introduction of interactive white boards in every classroom. This means lessons can be stored on the intranet and accessed by every teacher. "With the boards being internet and intranet-linked, and teachers being able to prepare in advance, lessons have become interesting, varied and interactive," says vice principal Vivienne Hughes.
The school has also used technology to overhaul registration. The system lets senior management see at a glance who is skipping lessons. Parents can also remotely monitor their child's attendance via the school website.
The school has also put student timetables, details of extra-curricular activities and homework online.
The school gives parents "247 reporting" with reports available to them directly via the internet, saving teachers work.
Mr Atkins also tackled the problem of cover. Each morning staff would go into the staffroom and look at a board showing who was absent and who would be covering for them "What other business starts its day on a negative?" he asked Now none of its teachers covers for absence. The job is done by five new cover teachers. Similarly, the school employs a small team of lunchtime supervisors, freeing staff from playground duties.
During the rest of the day, the supervisors make sure staffrooms are clean and stocked with tea and coffee. John Atkins says he is thinking of extending this role, to make supervisors "lifestyle managers" who will further lift burdens from busy teachers.
Another response to the teacher shortage has been to bring in double lessons in maths and ICT. A teacher prepares and teaches the lesson, while three assistants hand out pens, pencils and rulers - they also do all the marking.
In one Year 11 class, one teacher has taught 75 students with help from five assistants. The school expected some resistance to this from parents and students, but has so far had positive responses.
"Students say their needs are attended to much more immediately than when it's just a classroom teacher with a group of 30," says Vivienne Hughes.
"They can immediately start work - there's no time wasting." The assistants allowed the teacher to focus solely on producing a superb lesson.
Mr Atkins says all these measures have boosted efficiency: paperwork has been slashed and staff meetings whittled down to an hour a week.
Instead of evening parents' meetings, the school now shuts for two days a year to hold them in the daytime.
The aim of all this, says Mr Atkins, is to focus teachers' energy on teaching. The benefits are clear, mainly in terms of giving the school the ability to improve, he thinks.
Chair of governors Professor Mark Hector holds weekly meetings with Mr Atkins, and says he and fellow governors have played devil's advocate during what he admits has been a leap of faith for the school.
"We recognised that we had done as well as we could under the existing system. We thought there must be ways of making it a better school. The teachers really were fed up with all the extra duties. So we started working at ways of getting them away from those and letting them teach."
Name Kemnal technology college, Bromley
School type 11-18 boys' comprehensive
Proportion of children entitled to free school meals 21 per cent
Improved results The school has raised the proportion of students getting five Cs or better at GCSE from 7 per cent in 1990 to 50 per cent this year