For every five teachers in permanent jobs, with paid holidays and professional development, one teacher is on a temporary or fixed-term contract or doing casual supply work. They say they continue to be treated as second-class teachers - by staff and pupils.
A Scottish Executive-backed survey, carried out this year by researchers from London Metropolitan and Paisley universities, found that one teacher had worked in the same school for more than a year without a permanent contract. Some had been working in the same school for several years on temporary contracts.
Authorities are reviewing their practices after Glasgow lost a test case. A national review of temporary and supply teachers is under way in the Scottish Negotiating Committee for Teachers.
The survey found that 20 authorities employ 469 teachers as permanent supply staff to cover for absences in groups of schools. Almost half are in South Lanarkshire. The new system is said to be better for teachers and authorities, which are scrapping for staff.
But there are doubts. "This system may not be as successful as might be expected in creating sustained relationships between supply teachers and schools," say the findings, announced at the British Educational Research Association conference in Edinburgh.
The youngest teachers were most likely to be looking for permanent posts and 52 per cent of the entire sample of 699 teachers were unable to find the job they wanted. They accepted that supply teaching, often long term, offered them experience which might be helpful.
About a third of teachers said supply was their preferred option because of family commitments. Many of the more mature supply staff wanted a permanent job but intended to wait until a post came up in their local school.
Just under a third were in supply jobs to reduce their workload or top up pensions. Forty per cent of the sample had been in permanent teaching jobs immediately before supply work. Around 17 per cent had come straight from initial teacher training.
Younger teachers were most discontented. One said: "Cannot establish yourself as a teacher, no continuity, no experience of wider school issues, no experience in pastoral care system, no rapport with pupils established, no one to support you as a probationer."
Others noted the lack of belonging, never feeling part of a team, and finding it difficult to become involved in extra-curricular and whole-school activities. Another said there was no chance to see the long-term impact of their work and no satisfaction of watching pupils progress.
They also had difficulty planning their futures: "Don't get paid over the holidays, considerable variation in monthly wages, can't obtain a mortgage." Another said: "There is no progress, no career structure, no guarantees and often no continuity with class."
A particular concern was the lack of formal continuing professional development (CPD). "I was told it was only for permanent staff," one complained. Schools were unwilling to fund CPD because they were unlikely to benefit. Some local authorities expressed similar sentiments.
Secondary supply teachers were especially disaffected since they rarely taught their own subject. Only one in three normally taught their own discipline. Mostly they ended up supervising work set by a principal teacher.
Secondary supply staff felt they fell behind those in the first year of the new one-year, probationer scheme. No figures are yet available on the number of teachers who found permanent posts after their initial year.
The researchers call for special strategies to ensure that probationers on supply lists for longer are not disadvantaged as many have still to achieve full registration with the General Teaching Council for Scotland.
They also suggest better pay and a new career path in supply teaching for the most skilled and experienced to ensure they do more than "simply babysitting".
The study also unearthed a "chaotic and confusing" system for securing cover staff. Despite council-wide systems, individual schools ran their own lists because they wanted people they knew could bail them out at short notice.
Temporary teachers in Scotland and Cover TORY:contrasting systems of supply cover in England and Scotland will be published shortly by Merryn Hutchings (London Metropolitan University), Ian Menter, Chris Holligan and Liz Seagraves (Paisley University).