The 15 colleges, established at a cost to the taxpayer of more than Pounds 112 million with the promise that they would become "beacons of excellence" in the inner cities, are shown to have had mixed results in this year's schools and colleges performance tables.
Although the Government has abandoned expansion of the programme, preferring to boost technology education by funding specialist grant-maintained schools, the 15 colleges cost Pounds 48 million to run this year, receiving a further Pounds 4 million in capital grants.
The high cost of running them is bound to mean their performance will be closely scrutinised.
At Djanogly CTC in Nottingham, one of the first in which GCSE pupils have spent their entire secondary education in the new-wave colleges, just 16 per cent of pupils gained five or more A to C grades at GCSE, compared with the national average of 43.3 per cent and county average of 34.6 per cent.
Only just over a third of the 145 pupils taking vocational qualifications notched up success. A new principal has recently been appointed.
Djanogly is among five CTCs which fall below the national average for higher grade exam performance by pupils aged 16.
All five colleges also fell below the much lower average GCSE passes in their borough or county. Their achievements are modest despite operating the longest teaching weeks in the country.
The other four are: Bacon's in the London borough of Southwark, Harris and the Britschool in South London, and Leigh in Dartford, Kent. Each entered more than 100 15-year-old pupils for GCSE this year and all but Bacon's also offered vocational qualifications.
Sir Cyril Taylor, chairman of the CTC Trust, said: "The colleges that are not reaching national averages are mostly schools that we inherited. Schools we started from scratch can be measured as beacons of excellence.
"Once we have the first intake of our students there will be substantial rises in performance."
The most disappointing for ministers will almost certainly be Djanogly, purpose-built at a cost of almost Pounds 10 million and opened by former premier Margaret Thatcher, which teaches a 30-hour a week.
Nigel Akers, vice-principal, said: "The results were not unexpected .. . any institution, new school, finds in its first year that results would not be as high as later years. The curriculum was being invented, it wasn't something we could pull off the shelf and adapt. We had to adapt it looking at its success and failures.
"We are pleased with what we did achieve in our first year - it is comparable with other inner-city schools - and are looking forward to better results. "
At Bacon's, where pupils have been fined for smoking and chewing gum, 11 per cent of pupils gained five or more high grades at GCSE compared with the borough average of 18.3 per cent.
A spokeswoman said: "We are concerned that we are not reaching the national average. We know we have a long way to go."
Last year just six per cent of pupils at Bacon's, which opened in 1991, gained five or more GCSE grades A to C. At Harris CTC in Norwood, opened four years ago, 27 per cent of pupils gained grades A to C compared with the LEA average of 37.2, while the Britschool in Croydon achieved 31 per cent.
However, 91 per cent of the 81 Britschool pupils and 88 per cent of the 16-year-olds at Harris gained National Vocational Qualifications.
Nineteen per cent of pupils at Leigh CTC in Dartford gained five or more grades A to C, compared with the county average of 40.4 and more than three-quarters of pupils gained vocational qualifications.
Five CTCs achieved above average GCSE results - Kingshurst in Solihull, Haberdashers' in the London borough of Lewisham, Dixon's in Bradford, Macmillan in Teesside and Brooke in Corby, Northamptonshire. The remaining five CTCs have yet to produce comparable figures for GCSE because they have not been open long enough.