Part-time teachers have long been second-class citizens in school life. They arrive after all the best car-parking spaces have gone, they're deprived of a regular staffroom chair and they struggle to get to staff meetings in their own time. But it's time for an upgrade. In the business climate of today's schools, part-timers have first-class opportunities.
In the past, piecemeal timetabling often tied teachers to the school for much of the week, even if their contract was for only a few hours' teaching. Now many strike their own deals. This means compact timetables and a more focused contribution to daily routine.
Changes to employment law have increased rights and benefits for part-time staff, but the improvement in their position is down to a much older business law - supply and demand. Acute teacher shortages in specialist secondary subjects are allowing them to dictate terms.
"I teach a 0.7 timetable, but I wanted one day a week to spend at home with my child," explains one teacher at a large secondary school in South Yorkshire. "I teach some Spanish as well French, and while the shortage of teachers in modern languages is less acute than in some other subjects, it's not a common combination. When it came to discussing my timetable I was in a position to bargain."
Her head laughs: "To hold us to ransom more like. I'm not exactly wading through applications every time we advertise a post. I'd be failing in my duty if I didn't do everything possible to secure the best staff. So when we find someone we want, we'll bend over backwards to accommodate them. It can turn the timetable into one hell of a jigsaw puzzle, but such is life."
Teacher shortages have led to a crisis in many schools, with well-publicised tales of heads employing unqualified staff, appointing without interviews, recruiting from abroad or resorting to a four-day week. Some schools have "gazumped" rivals to secure the services of teachers in crisis subjects.
But for part-time teachers, it is working hours that have become the battleground. While they have been able to address some issues such as pay for attending training days or staff meetings, what they are holding out for is compact timetables that mimimise their hours in school.
Teaching unions welcome what they see as a long-overdue shift in the balance of power. "There's no point in heads getting in a sulk if Mrs Jones says she won't work Fridays or whatever," says a spokesman for the National Association of Schoolmasters Union of Women Teachers. "Market forces dictate in every area of our life. The days of slavery and mill-owners are gone and schools had better wise up to it."
Dennis Richards, head of St Aidan's C of E school in Harrogate, Yorkshire, points out that successful timetabling can be critical to a child's progress. It is not simply a case of heads sulking, it is trying to find a balance that suits the teacher without disrupting learning.
"The demands of part-time teachers re not unreasonable," he says. "If I were in their shoes I'd be doing exactly the same. But about a fifth of our staff here are part-time and if they all start saying they will work only on certain days, you will inevitably have to split a class. It's not very satisfactory when a class ends up with more than one teacher.
"The timetable used to revolve around the full-time staff, with part-timers plugging the gaps. But now it's come full circle. The demands of the part-time teachers have to be met first."
The shift from timetable Polyfilla to foundation stone has even enabled some part-time teachers to find work in more than one school. They mix and match commitments to come up with a flexible combination that works. One geography teacher in the West Midlands explains how he combines a 0.3 timetable in one school with a 0.4 timetable in another, half an hour away.
"I'd been working the 0.4 shift for a couple of years when the second job came up. I said I'd do it if they could fit me in. And they did. Most of the time it's straightforward - a morning here, an afternoon there.
"People always assume that if you're part-time it's out of choice. But some part-timers would like more hours. If you can squeeze a better deal out of schools in terms of working complete mornings or afternoons, a second or even third contract is a real possibility."
But before you rush to exchange full-time drudgery for part-time flexibility, make sure you consider the potential pitfalls. Dennis Richards says: "Legal changes that have given part-time workers the same rights as full-time staff could ultimately count against them. Heads could opt for short-term contracts of less than a year or supply teachers, rather than give a permanent part-time contract with all the rights that go with it."
It's a problem the unions have recognised. The National Union of Teachers insists that short-term contracts should be used only for specific periods of absence or need - such as maternity leave or extended training - not as an attempt to dodge legal responsibilities. "The rights now enjoyed by part-time teachers are entirely reasonable," says an NUT spokesman. "If schools resent those rights, it's deeply disturbing.
"One case we're dealing with involves a part-time teacher whose area of responsibility was singled out for praise by Ofsted. That led to her being head-hunted by another school that had an inspection on the horizon. She took the job, took them through the inspection - then they dropped her."
If part-timers are seen as the answer to staffing shortages, they may also find themselves dispensable when the tide turns. Those who were in a position to strike a hard bargain may be left high and dry by the ebb and flow of the labour market.
"Part-time staff are at the volatile end of things," says Brian Carter, the NUT's regional secretary for the Midlands. "When demand is high, as it currently is, they are the ones who benefit most. But eventually something will have to be done about staff shortages. That's when part-time teachers will feel a backlash."