Spending on education will fall by more than 13 per cent over the next four years, according to a report.
Research by the Institute for Fiscal Studies (IFS) says it will be the biggest cut for more than half a century.
School building programmes, universities and provision for the under-fives and 16 to 19-year-olds will be worst-hit.
"The key question is what these cuts in resources will mean for the outputs of the education system – such as young people's exam results or earning potential," said Luke Sibieta, of the IFS.
"The cuts will be deepest for capital spending and higher education," says the IFS. By contrast school spending is "relatively protected" although those in the more affluent areas will see real-term cuts.
Only those in the most deprived areas will see an increase – largely as a result of the Government's decision to award schools a "pupil premium" for those pupils entitled to free school meals.
The trend is in stark contrast to the previous decade when it saw the fastest growth period for 30 years – rising from 4.5 per cent of the national income in 1999/200 to 6.4 per cent in 2009/10. Then it was school building programmes and early years spending which secured much of the extra funding.
Education's share of GNP will be levelled at 4.6 per cent by 2014/5, the report says.
The public sector pay freeze will aid school budgets by ensuring costs rise at less than inflation, the report goes on.
A Department for Education spokesman said: "The Government had to take tough decisions to reduce the deficit but the schools' budget is actually increasing by £3.6bn over the next four years.
"The Government was absolutely right to look at the amount of money spent on school buildings. An independent review showed that taxpayers' money was being wasted on red-tape and consultants."