John Peckham had to send out begging letters to parents to try to stave off an pound;80,000 budget deficit.
But even though his school, Bramhall high, in Stockport, serves an affluent area, only about 10 per cent of parents responded positively.
Mr Peckham laid the problem out bluntly to parents. "I wrote telling them to be prepared for bigger classes because the only way left for us to make savings was through salary cuts."
About 10 per cent of Bramhall's 1,100 families have taken out covenants, bringing in pound;14,500 a year. The school has suggested a pound;10 a month pledge, though amounts vary per family.
A further 230 families make one-off donations of pound;10 a year, helping to to sustain sports clubs and activities at the school which has 1,400 pupils.
Just 4 per cent of Bramhall's pupils are on free school meals and the school has a 74 per cent success rate at five or more top grade GCSEs.
"We are not eligible to bid for any pots of money such as incentive grants or Excellence in Cities," said Mr Peckham. "But our children still need classrooms and roofs over their heads."
He has sympathy with parents who feel ideologically opposed to contributing financially but said: "I've told them that I can only structure the pupils'
education according to what resources I have. It would be a shame if a school such as ours, with its history of excellence in music and drama, should suddenly have to introduce an austere curriculum because that is all we can provide.
"But that is the stark reality. Either the parents help us, or we have to make do with what we can provide. It does seem amazing that more than half of families make no contribution, even though they can afford to. They seem quite happy to drop their children off in the morning in their BMWs and drive off."