Nearly all Tony Blair's flagship city academies were named among the worst schools in England in league tables published today.
Nine out of the 11 city academies that reported test results for 14-year-olds in English, maths and science came in the bottom 200 schools in England.
Another six academies opened too recently to take part in the tests.
In the Capital City Academy in Brent, north London, just 28 per cent of pupils reached the level expected of their age group in English, 35 per cent in maths and 23 per cent in science.
The national averages were for 73 per cent of pupils in England to reach Level 5 - the standard expected of 14-yearolds - in English and maths, and 68 per cent in science.
Teachers' leaders called on Education Secretary Ruth Kelly to reconsider her target for creating 200 city academies by 2010.
Steve Sinnott, general secretary of the National Union of Teachers, said: "This is an experiment with children's futures which is not promoting their best interests and is damaging to the other schools around them.
"It is high time the Government reconsidered the strategy which is benefiting no-one and using up a disproportionate amount of funding." In exchange for £2 million, private sponsors get a major say in the running of a city academy, including setting the school's overall ethos.
The rest of the costs for setting up an academy are paid by the Government, typically totalling £25 million, although academies are independent of the rest of the state sector.
Eight other academies also came in the bottom 200 schools out of more than 3,000 included in the tables for their 2004 Key Stage 3 tests.
The schools were ranked on Government figures for the average points scores achieved by pupils in the tests.
These included a school that Tony Blair hailed as "the future" of secondary education when he opened it - the Business Academy Bexley, in Kent.
The figures showed that 14-year-olds at the Capital City Academy on average failed to meet the levels expected of 11-year-olds in the three subjects.
But a spokesman for the DfES insisted academies were making "big strides" in a short space of time.
"Academies are a new type of school in some of the country's most economically and educationally disadvantaged areas, reinvigorating education and, in many cases, replacing schools which have failed their pupils for several generations.