A head teacher today claimed his school could be forced to increase class sizes because it was being "crippled" by school funding policy.

John Patterson, head of Bingley Grammar School, said the secondary would face a budget deficit of £300,000 if classes remained at their present sizes.

And Mr Patterson, pictured, said that if class sizes had to be increased, standards would be difficult to maintain.

The head teacher has written to the parents of the 1,850 pupils at the school, urging them to fight for more funding by writing to Bradford Council education chiefs, Bingley councillors and local MP Chris Leslie.

Mr Patterson said the school was one of the worst-funded secondary schools in Bradford because it did not suffer from social deprivation.

He said annual funding was "quite rightly" weighted according to social need but he claimed more weighting was also given to primary schools.

"The double weighting in favour of both primary schools, and schools in deprived areas, has disastrous results for Bingley Grammar School's annual budget," said Mr Patterson in the letter.

In the letter he also claimed:

l some Bradford schools receive up to £1,800 per pupil more than Bingley Grammar

l the school's tutor group sizes could increase from an average of 28 to 34

l the school has campaigned for more than 12 months but has not been given assurances the situation would improve.

Mr Patterson said: "The system means that schools such as ourselves and Ilkley Grammar School find that they don't serve areas of social deprivation and we don't get the money we need to run.

"We are facing a projected budget deficit for the next year of £300,000.

"The school has never in its history had a budget deficit but next year it could have one."

The school has also organised a petition calling for funding.

Phil Green, Bradford Council's director of education, said the distribution of school funding was determined by the Fair Funding Formula agreed by the Schools Forum, made up representatives of schools, Bradford Council and Education Bradford.

Mr Green said: "The Council has made considerable efforts over the last five years to improve the levels of funding to schools and while there is still a gap between the levels of funding for schools and the DfES recommended levels it has narrowed by more than half.

"There is £17.8 million extra going into schools in 2005 and 2006 and Bingley Grammar will benefit along with all schools in the district."

Councillor Dale Smith, executive member for education, said: "I have received some letters from parents of children at the school into its funding and I am replying to each one."