One in four children attending nursery are in a "teacher-free zone", according to the head of Scotland's largest teaching union as it prepares to mount a battle to raise teacher-involvement in early years education.
In council-run nurseries, the figure is one in 20 children (5.1 per cent) with no access to a teacher, despite Government commitments to universal access.
In private nurseries run in partnership with local authorities, it is 49.5 per cent, research published today by the Educational Institute of Scotland shows.
Despite the Government's commitment in its concordat with local government to give every child such access, the number of nursery teachers has dropped significantly and many are employed on an ad hoc, fragmented or part-time basis, says the EIS.
The figures are contained in a new report commissioned by the union and written by its former education convener, George MacBride.
It warns that the early years sector is particularly vulnerable to cuts by cash-strapped councils because there is no statutory obligation to involve teachers in pre-school education.
Ronnie Smith, EIS general secretary, argues that teacher involvement in all nursery settings is particularly important, now that Curriculum for Excellence has moved to a seamless model from 3 to 18.
"Without teachers in all nursery schools and nursery classes, there is the risk that this important early stage of CfE will start to unravel, which will cause greater difficulties for children and their teachers once they reach primary school," he said.
The report highlights variation of provision across authorities and sectors: in 13 councils there are no peripatetic or shared nursery teachers working in partnership centres. According to 2009 pre-school census figures, only 13.3 per cent of children in the Western Isles have access to a teacher under a regular arrangement, compared to 98.1 per cent in West Lothian.
Teacher access is higher in council-run nurseries but the figures still show low teacher involvement in some authorities.
In Argyll and Bute, 25 council nurseries are supported by one whole-time equivalent teacher - in reality, some 20 teachers each employed for only a few hours per week. This is neither "meaningful" nor "coherent", said Mr Smith.
A spokesman for the Scottish Government said it had expanded the legal entitlement to nursery education to 475 hours per annum and several councils were already delivering the next phase of expansion to 570 hours.
Over the last two years, under the concordat, over 9,000 more children had access to teachers in pre-school settings, which represented "steady progress against a worsening financial picture".
"There is no robust evidence on the amount of teacher time which is needed to improve children's outcomes but we are clear that occasional or ad hoc access is unlikely to achieve such improvements," added the spokesman.