A Dorset supply teacher’s three-year battle for a fair pay rate illustrates the widely varying conditions such staff face nationwide. It is a situation described by one senior union official as “the Arthur Daley school of employment”.

When Janet Clayson moved to Dorset three years ago, she was shocked to find that schools there appeared to be paying her pound;6 an hour less than she had been getting in Battle, East Sussex.

“I took early retirement a few years ago to escape the stress of full-time teaching,” explains Ms Clayson. “I worked out that I could survive on my supply earnings. So to come down to Dorset and find I was getting pound;30 less a day was rather a blow.”

Although Ms Clayson regularly arrived at 8.30am to prepare her lessons, stayed on after school to mark work and once wrote a history syllabus at home, it transpired that some schools were only paying her for the time she spent actually standing in front of a class. While she understood a day’s work to mean at least six hours, some schools were paying her for as little as five. To add insult to injury, a few schools determined her pay rate retrospectively, deciding on the number of hours she would be paid after she had left, or changing the number she had originally claimed.

According to Vince Allen, a regional official with the National Union of Teachers in the South West, there is a wide disparity in pay rates for supply teachers, even when they are directly employed by local education authorities or schools. East Sussex and most other authorities work out pay by dividing a supply teacher’s full-time equivalent salary by 195, the number of days teachers are contracted to work per year. For a teacher at the top of the scale, such as Ms Clayson, this works out at around pound;135 a day.

But to save money, some schools and authorities use an hourly rate based on the 1,265 hours of “directed time” in a full-time teacher’s contract; this works out at 6.5 hours a day, and allows schools to say they will not pay for any preparation or marking, lunch breaks or even, in the case of one Dorset school, mid-morning breaks. For many Dorset schools, a supply teacher’s day is only 5.5 hours, so the authority only has to pay pound;115 to a teacher at the top of the scale.

“We do urge teachers to try and insist on the 1195 method of payment,” says Val Shield of the Association of Teachers and Lecturers. “This compensates for the lack of holiday pay. If schools and LEAs aren’t paying supply teachers properly, what hope is there for fair treatment from private agencies?”

One knock-on effect of refusing to pay for preparation or marking is the extra burden facing a teacher returning from sick-leave. “Teachers who have been off with a stress-related illness return to be greeted with a huge backlog of work,” says Vince Allen of the NUT.

Using the Part-Time Workers’ (Prevention of Less Favourable Treatment) Regulations, the union has presented a claim on Ms Clayson’s behalf to an employment tribunal. The chair of the tribunal has now told the union and Dorset to go away and work out a satisfactory solution.

Dorset claims it cannot tell the schools how to pay supply teachers, as the schools are the employers. But it has insisted that they explain what they are going to pay before teachers agree to take on the work. “Normal mid-session breaks” must also be included as part of the hours offered, Dorset says.

“We do not direct schools specifically in determining the individual working hours of a supply teacher,” a spokeswoman said. “The LEA has issued revised guidance clarifying the question of full and part day working and advises its schools to be clear with the supply teacher as to the basis and duration of each engagement at the outset.”

Graham Clayton, the NUT’s senior solicitor, says the fault lies with the scanty references to supply teachers in the teachers’ pay and conditions document, which people can choose to interpret differently.

That document states that a supply teacher’s day should be paid on a daily basis “calculated on the assumption that a full working year consists of 195 days”. A working day should be “considered to be 6.5 hours (including an allowance for duties other than teaching pupils)”. But “teachers who cannot be available for work beyond the pupil day” can be paid at an hourly rate.

The reality is that conscientious supply teachers will continue to do all the extra work without remuneration.

“What is really wrong is that a lot of them go in early, stay late and liaise with other staff, yet are not being paid for it,” says Anita Mitchell, chief executive of Go Teaching, a supply agency that charges a modest, flat-rate fee for supplying teachers on behalf of many authorities in the South West.

Ms Mitchell says that her agency advises schools to pay for 6.5 hours if they want someone to do a proper job, but many say that they cannot afford to do so. She points out that, in other areas, where teachers are harder to recruit, they are generally treated much better. It seems that the free market will continue to work unfairly for supply teachers.