Parents spend almost pound;1,000 a year putting a child through secondary school and a quarter of them struggle to pay, a government survey reveals.
It details for the first time the amounts parents are paying towards uniforms, sports kit, class materials, trips, school photos, meals and transport.
Research conducted for the Department for Education and Skills also discloses the pressure that parents are under to contribute to school funds and charity events.
And it shows how far children are going to safeguard their parents, with one in three saying they do not always pass on school letters seeking cash.
The survey of 1,500 parents shows that they give an average of pound;25.32 a year to school funds and another pound;11 to charity events annually.
This is part of a pound;948.11 annual bill facing parents for every secondary pupil. Parents with children in primary school pay out pound;563.15 for each child.
More than a quarter of parents (27 per cent) said they found it difficult or very difficult to meet these costs. More than half were families with income below pound;15,000, the official poverty line. Child benefit of pound;16.50 a week for the first child, and pound;11.05 for others, is not enough to meet secondary school costs and would only just cover primary costs.
The Cost of Schooling survey shows the largest expense for parents is meals, costing an average of pound;1.66 a day or pound;316.20 a year.
Uniforms and PE kit for secondary school boys averaged pound;312.85, compared with pound;216.08 for girls. In primary school, such costs are more equal at about pound;172.
Parents who contributed towards class materials reported especially high bills for music lessons (pound;70), cookery (pound;39) and technology (Pounds 20.25).
The 280 schools which were sampled at the same time denied costs were so high.
A report by the National Confederation of Parent Teacher Associations in September found that parents propped up school budgets to the tune of Pounds 68.5 million last year. It showed each school raised an average of Pounds 5,400.
Citizens Advice now wants the Government to introduce statutory funding for uniform grants.
Katie Lane, social policy officer, said: "For many families uniform spells debt, distress and discrimination. The Government must act to ensure all parents on low incomes can get help with costs."
The Hertford Trust provides pound;6,500 funding for parents in Bedfordshire every year. Its most recent survey shows that uniforms, visits and school events cost parents pound;500 per child every year.
David Russell, chief executive, said: "Our grants just scratch the surface.
Twenty times that number of families need help.
"We are working with schools to find commonsense solutions to keep costs down, such as getting rid of blazers and expensive stitched logos, and requiring items that can be used at all stages of schooling."
The Hertford Trust plans to make advice available to parents and schools on DVDs next year.
The Cost of Schooling is available from DfES Publications, PO box 5050, Sherwood Park, Annesley, Nottingham. Price pound;4.50.