Variations in school cash queried
England's school funding system needs an overhaul and should be investigated by the National Audit Office, the Liberal Democrats have said.
Education spokesman David Laws drew attention to the way schools in Labour-controlled local authorities had received more money than others.
In Labour Middlesbrough spending on schools has grown 54% since 1997, in Tory Bournemouth the rise was 27%.
Mr Laws said the funding system was poorly understood and illogical.
He said he would be writing to the National Audit Office asking them to look at the variation in funding increases across England.
In Middlesbrough's case, the rise had been £1,701 per pupil since 2007, from £3,136 to £4,837.
In Bournemouth the difference was £844 or less than half as much, from £3,147 to £3,991.
Deprivation
Mr Laws said: "It is notable that Labour-controlled areas seem to have the biggest increases in funding, and this raises concerns about the fairness of the way in which cash is allocated.
"The funding of schools is crucial to the prospects for young people, and it must be fair.
"The existing system for funding schools needs a radical overhaul, as it is poorly understood and often illogical."
The obvious explanation for the disparities is that Labour has targeted the greater share of the extra money it has put into education on the most needy parts of the country.
A spokesman for the Department for Children, Schools and Families said it wanted all children to have an equal chance to succeed.
"Children from disdvantaged backgrounds are more likely to need extra support from their school to make that a reality.
"That is why funding levels reflect disadvantage in each area."
But Mr Laws said the existing system was too crude: there was a real problem in targeting the many deprived youngsters who did not live in areas which were classified as being disadvantaged.
