Parents have hit out after more than 100 teaching jobs were cut in the North-East at a time of record school staffing elsewhere in the country.
A number of schools around the region will be making teaching and support staff redundant at the end of the year, while many more will not replace members of staff retiring or quitting the classroom.
The situation has been blamed on a drop in school budgets caused mainly by falling pupil numbers.
But parents' groups have joined teaching unions in criticising the Government's school funding system for adding to the problem.
The loss of teaching jobs in the North-East comes in contrast to the situation in the rest of the country, where classroom staffing levels have reached a 25-year high.
Howard Brown, of the National Union of Teachers, said: "For the first time, teachers are being made redundant while there has been a big increase in the wage bill for non-teaching staff.
"That's down to the Government's re-modelling of the workforce which is seeing support staff take over work previously done by teachers. If that continues, it could have a major detrimental effect on the education of children. In any sensible society, the Government would make sure smaller class sizes became a reality rather than a dream but because of the way schools are funded, it can't happen. It's all to do with economy now, no longer quality."
Margaret Morrissey, of the National Confederation of Parent Teacher Associations, said: "From a parent's point of view, it doesn't matter that a class of 16 doesn't qualify for a teacher. All they know is that those 16 children still need to be taught.
"We've always said that funding for teachers shouldn't be tied to the number of children. Funding should be for the number of classes - it's the only way to resolve this issue."
At the end of April, then Schools Minister Jacqui Smith announced a 3,500 rise in the number of teachers working in England.
But the North-East was the only part of the country to cut staff. More cuts will come over the next few months, with the biggest losses in Sunderland, with 47 voluntary redundancies, and Newcastle, which is shedding 16 jobs at end of the academic year with similar numbers expected in December. A total of 10 schools in Northumberland have redundancies notices, although it is hoped there will be only eight compulsory redundancies, while both South Tyneside and County Durham will have to lose 12 teachers. Figures were not available last night for Gateshead or North Tyneside, though both authorities are hopeful of keeping any cuts to small numbers.
A DfES spokesman said: "The number of teachers needed over time will vary from one area to another and schools and local authorities will need to decide how they manage numbers of teacher and support staff posts on the basis of anticipated local needs.
"Around the country, teacher numbers continue to rise - by 3,500 in the last year alone - as do support staff numbers. We have more teachers than at anytime since 1980 and more support staff than ever."