More than 350 extra teachers could be hired with £9m that schools in Harrow had tucked away in their coffers.


Figures obtained by the Observer show that the borough's headteachers carried over vast unspent sums from one financial year to the next at the end of March, the average being £136,357.


Bentley Wood High School for Girls in Bridges Road, Stanmore, had the most in its bank account - £650,770 - while the second highest figure was found at Norbury, Welldon Crescent, Harrow, with £545,310.


Nower Hill High School in George V Avenue, Pinner, ended 2007/08 with the lowest balance of any school, £11,003, and the second least - £11,881 - belonged to Kingsley High School, a special school in Whittlesea Road, Harrow Weald.


The accumulative £9.1m that schools had left over would pay for 378 newly qualified teachers on a London-weighed salary of £24,168 a year.


The figures were released after a request under the Freedom of Information Act.


Mark Wallace, campaign director of the Taxpayers' Alliance, said: "These budgets are provided for the education of the children currently at these schools and so I think parents will be understandable aggrieved if they found out the money is being salted away somewhere.


"Such a practice makes it difficult for schools to say they need to have their budgets increased when they're not spending the money they have been given."


In October last year, the Government scrapped a plan to allow councils to claw back unspent money in school bank accounts and redistribute it locally.


The policy would have compelled authorities to seize any excess over five per cent of a secondary school's budget and eight per cent of a primary school's - totals set down by the Audit Commission.


But in Harrow, schools with bank balances higher than these are required to submit a return to Harrow Council showing a breakdown of the proposed use of the balances.


Heather Clements, director for schools and children's development, said: "Schools carry reserves from year to year in order to have a contingency against unexpected costs such as long-term absence of staff, increased pupil numbers and unexpected building costs.


"In addition, some schools hold funds on behalf of their extended schools clusters or for other partnership projects which are spent over an academic year rather than a financial one. 


"Schools will sometimes accrue funding for specific projects, which may take more than one year to fund - new IT equipment is a good example of this. In some schools balances may be larger in any one year because of these particular circumstances.


"We are satisfied that schools in Harrow have robust financial management systems in place to ensure that children receive the best possible provision and their needs are met."