The dilemma is that councillors could lose not just their credibility but Pounds 12 million in Scottish Office money given to upgrade school buildings on condition they reduce the city’s 17,500 surplus secondary places, which the proposals will cut to 5,000.

If the plans start to unravel, an anticipated Pounds 40 million in private funding for new schools, new technology and clearing the maintenance backlog, which has to be approved by the Treasury, is unlikely to materialise either.

But parents, with long memories of past closure debacles, were not reassured by the council’s undertaking that the full Pounds 7 million saved from closures over the next five years would be ploughed back into education, giving Glasgow the best instead of the worst pupil-teacher ratios in Scotland by 2002. “That is not an assurance I could have given before,” Mr Corsar said. “I have heard all that rubbish before,” he was told.

The North Kelvinside meeting was particularly unimpressed by Mr Corsar’s arguments that pupils would have more subject choice in larger schools. “There is no such thing as one type of identikit school,” Usha Brown, a parent, said. “Some big schools are good. Some small schools are good. What is needed is to support good schools.”

Jaimie Webster, another protester, said there was no support for creating a 1,300-pupil school “like cramped sardines in a tin” on a site at Cleveden. The logic of the council’s approach was in one speaker’s view “to have one big secondary for the whole of Glasgow”.

Mr Corsar’s plea for parents to concentrate on the big picture rather than oppose closures on the nimby principle (“not in my backyard”) also fell on unresponsive ears. “Glasgow is my back yard,” Jane Macaulay, a local parent, declared.