The government has for the first time released swathes of data for England's state schools, showing funding and expenditure per pupil, and how the money is spent.

Education Secretary Michael Gove has urged parents to "go compare", hoping the information will lead to a push for value for money.

But one teachers' union said the information was more likely to confuse than inform, and that parents should be encouraged to become more involved in their children's schooling in general - rather than to become "amateur auditors".

The BBC News website looks at what the data does and does not show.

PER PUPIL SPENDING

Figures are given for per pupil spending for primary and secondary schools in 2009-10. They show huge variations - between £1,500 and £33,000 for secondary schools (£1,000 and £17,000 for primaries). These are the extremes, but there are still wide variations between funding - secondaries tend to fall between £4,000 and £9,000, primaries between £3,000 and £8,000. However, the data is not given for academies, which are outside local authority control and have larger budgets, so the figures do not give the whole picture.

FUNDS RAISED BY SCHOOLS

However, this does not mean the schools spending most are necessarily those that get the most government funding. The figures also give the proportion of income that each school generates itself - perhaps from donors, endowments or an active Parent Teacher Association.

On average this is just 4%, but it varies widely. The secondary school that generates the highest proportion of its own income - Old Swinford Hospital, a state boarding school in Dudley - raises 63% of its income itself. For primary schools, Petworth Church of England school in West Sussex, and Heather Primary School, Leicestershire, top the table, both raising 42% of their own funding.

DEPRIVATION FUNDING

The data reflects what is already known - that the existing schools' funding formula allocates higher levels of money to areas with higher deprivation. The government has banded schools into three categories. For example, for secondary schools, the median funding for areas outside London with low levels of deprivation is £5,021, rising to £6,849 for high levels.

REGIONAL VARIATIONS

The figures also give average grant funding for schools in each local authority. Schools funding includes a London weighting, so unsurprisingly, areas in the capital lead the table.

The secondary schools list is topped by Tower Hamlets (£8,058 on average per pupil), followed by Hackney (£7,962) and Lambeth (£7,207). Knowsley in Merseyside receives the lowest, (with £3,790), followed by Solihull (£4,445) and Swindon (£4,563).

At primary level, the Isles of Scilly (£8,736), City of London (£7,401), and Tower Hamlets (£5,967) top the table, with South Gloucestershire (£3,328), Central Bedfordshire (£3,354) and Solihull (£3,432) at the bottom.

However, comparing these figures may be misleading, because of the exclusion of academies. A proportion of local authority funding is held back from most schools to provide services - for example support for children with special educational needs - at local authority level. But academies get access to their own share of this money, which can push their budgets up by 1% to 15%. Therefore, if a local authority has a lot of academies, it may spend more on its schools than the data suggests.

WHERE THE MONEY GOES

The new figures also show what schools spend their money on - with teaching the largest category, taking up on between 73% and 23% of primary budgets, and 73% and 27% of secondary budgets.

However, other expenditure areas also vary widely from school to school - for secondary schools, premises costs range from 43% to 0%, back office costs from 33% to 2%, energy from 8% to 0%, and ICT from 7% to 0.

This information is also available at local authority level - showing, for example, that, Birmingham devotes the highest proportion of school spending to back office costs of all the local authorities (18% of expenditure for secondaries and 15% for primaries), while Wakefield and St Helens spend the least in this category for both primaries and secondaries (4 - 6%).

The government hopes the publication of the data will lead parents, local media and interest groups to be more assertive in demanding value for money - while there may be wide ranging explanations for what the data shows, it is more information than has ever been publicly available before to help them work out what questions to ask.