Part-time teachers are on the up. Numbers are at a record high, with nearly 80,000 employed in England and Wales. This represents a 28 per cent increase since 1997 - over the same period, the full-time workforce has grown by a mere 1 per cent.

Is this rise a sign that modern “flexible” working has arrived in schools? Can the Government, with its talk of work-life balance and family-friendly jobs legislation, celebrate? Despite the fact that part-timers now account for about 15 per cent of teachers, the answer, alas, is not yet.

John Howson of Education Data Surveys, says the 2003 reform that gave parents of young children the right to request flexible work has yet to have a real impact in education where the majority of part-timers are over 45. He believes that schools’ lack of money is the main reason for what some say is a “casualisation” of the workforce. Primaries in particular are being hit by falling rolls, and are cutting back on staff. Rural authorities, such as Cumbria, employ a high proportion of part-timers.

“Half” a teacher can make a big difference in a village school.

Another reason is stress. Workload drives some full-timers to cut back, says John Bangs, head of education at the National Union of Teachers.

“Teachers used to go part-time because they wanted to do something else.

Now they do it because the job is so intense.”

But going part-time - even if pushed - is not an escape from the pressures of work. Job insecurity is one problem. Many part-timers are on fixed-term contracts and are “let go” when pupil numbers drop further. Exploitation is another. More than 90 per cent of part-timers told the NUT in 2001 that they had a full-time workload. Two-thirds of them also said they suffered discrimination. John Bangs says nothing has changed.

Such problems stop teachers with positive reasons for going part-time from applying, says Ken Savage, director of Flexecutive, a job agency specialising in flexible working. “A hell of a lot of people” want to make the change - there are never less than 4,000 teachers on his register - but fear of being marginalised prevents them, he says. Only a third of heads are in favour. Another third is ambivalent and the rest, usually the older male managers, would rather have a long-term vacancy than employ a part-timer.

Education is the “last bastion” behind the private sector and the health service in its attitudes to flexible working, says Mr Savage.

Reforms, such as reduced working hours and self-rostering, are being introduced into the NHS in order to hold on to its largely female staff.

Education, however, is still waiting. In the Netherlands, 50 per cent of upper secondary teachers work part-time. The figure for secondary teachers here is under 10 per cent.

The Government acknowledged two years ago that the “practices are still not widespread enough, and women still want to see more flexible working and training”. It quoted a teacher saying: “Schools don’t like part-time teachers. They say it never balances out. It costs more money.”

Dr Maggie Moyo-Robbins of the University of Central England, who has been tracking 84 primary teachers since they graduated from UCE in 1996, confirms this. She says that part-time, temporary and supply teachers have limited career development, poor status, and reduced access to training and to professional development. “All such teachers in my research said that they generally felt marginalised.”

Dr Robbins says that the status of the “flexible” teacher needs to rise.

Training and professional development must go with the job, so that the employee can see his or her career advance. He or she must be engaged fully in school policy and curriculum developments and not left on the margin.

Flexecutive is eager to spread good practice. It works with about 15 local authorities - all committed to the principle of flexible employment. The key to winning over reactionary heads, says Mr Savage, is explaining that part-time work - and certainly job shares - can be a win-win situation in both primary and secondary schools. The Office for Standards in Education, for example, estimated that a job-share team is between 20-30 per cent more productive than a single teacher. And a part-time deal is a good way to retain scarce teachers - and might have kept some of the half-million staff who have quit over the past decade.

Flexecutive advises teachers and schools on potential stumbling blocks.

While recent legislation has given part-timers equal rights with full-timers, many niggles remain. For example, a part-time teacher must currently opt into the pension scheme, but her full-time colleague is automatically a member. Issues of training, timetables, timing of staff meetings and parents’ evenings - never mind assessment and promotion - can all cause resentment. For Ken Savage the solution is that “everything is pro-rata-ed, including management allowances and training. And everything is dealt with clearly from the start”.

Communication is the key - particularly when it comes to job-sharing. “You must not enter into these arrangements lightly. It is like a marriage, and can last for years,” says Mr Savage.

One head who has arranged several “marriages” is Angela Mills of Meridian primary in Peacehaven, East Sussex. She welcomes job-sharing teachers and her staff of 10 currently includes two teams. She says she gives 110 per cent to them - and gets it back. “I have two fresh teachers, instead of one exhausted one. I don’t lose amazing and wonderful teachers when they have a baby. And I can play to their strengths - for example, pairing a science and maths specialist with someone whose strengths are in literacy and PE.”

Her part-timers know what the deal is when they join. “I make it all really clear. They are busy people and they need to know what is expected,” she says.

Potential gripes are dealt with. Part-timers get the same amount of in-service training as full-timers. Mrs Mills has a staff-care policy and is very parent-friendly. Teachers get time off to visit schools for their own children, and flexitime in the morning if their youngster is sick.

Job-sharers are given two hours a week to liaise about their class. Some heads are reluctant to pay for this “overlap,” but Mrs Mills considers it vital.

All in all she says a job share costs the school about an extra pound;1,000 a year. She reckons it is money very well spent.