Buildings at Durham Johnston school are so out-of-date that A-level students have to be taught in a pair of Victorian houses originally built as an orphanage.
The successful comprehensive, which is on a split site, has a leaking kitchen roof, rotting window frames and 16 mobile classrooms which are up to 20 years old.
It is among a quarter of English secondaries found by inspectors to have inadequate facilities. Buildings and grounds are unsatisfactory at almost one in 10 primaries.
Labour came to power in 1997 promising to tackle a "pound;3 billion backlog" in school repairs, and capital spending in England doubled to pound;2.6bn a year between 1998 and 2004.
But Carolyn Roberts, head of Durham Johnston in County Durham, said her school's exam success - 65 per cent of pupils gained at least five A*-C GCSEs last year - meant it had missed out on the national investment.
Extra resources, including the Government's multi-billion Building Schools for the Future programme, have been targeted at struggling schools in poor areas.
Even John Dunford, former head of the school and now general secretary of Secondary Heads Association, failed to get cash from local or central government to pay for much-needed work.
Mrs Roberts said: "Our buildings are not fit for modern purposes. The local authority is trying to raise money to get work done by 2008. If we had to wait for our turn from the Government it would be another 12 years. We cannot wait that long."
Inspectors say that the state of school buildings nationally is hampering the range and quality of the curriculum in primaries.
Access for disabled pupils also remains a problem despite extra funding and a legal obligation to open up schools to pupils with special needs. Ofsted also highlighted unsatisfactory PE facilities and science labs in secondaries.
Facilities in a quarter of pupil referral units and one in three schools for pupils with severe learning difficulties, emotional, behavioural and social difficulties are unsatisfactory.
Ofsted's report follows official figures which show schools and councils face a bill of almost pound;8 million over the next five years to improve premises. They reveal 14,000 temporary buildings are still in use.
Ministers have promised to increase spending on school buildings to Pounds 6.3bn by 20078. But a promise to rebuild or refurbish all English secondaries by 2015 has been downgraded to a pledge to start rebuilding at least three schools in every authority.
David Hart, National Association of Head Teachers general secretary, said:
"It is pretty appalling that in 2005 we still have such a large number of schools with inadequate facilities. The Government's capital spending programme will do a great deal to change this in secondaries but I remain to be convinced it has put enough aside for primaries.
"Primary schools are treated as second-class citizens when it comes to spending on facilities."
Key primary problems
* a lack of outdoor space for learning areas and physical education
* poor information and communication equipment
* particularly poor facilities for the youngest children@Sansfullrr = Key secondary problems
* a quarter of PE facilities and a sixth of science labs are unsatisfactory, despite improvements in recent years
* poor maintenance of old buildings
* some classrooms are too small or unsuitable for practical work