PHOENIX high - the west London school lauded as a pioneer of New Labour policies - has made much progress, says an Office for Standards in Education report.
But it still has some serious flaws, such as unsatisfactory teaching and poor attendance.
Phoenix rose from the ashes of a failing school and has been promoted by the Government as a successful example of a "Fresh Start" school.
However, according to its high-profile head, William Atkinson, the school still struggles to attract teachers, despite its improving reputation.
The report says the 11-16 comprehensive in Hammersmith and Fulham is extremely well led and rigorously managed. Pupils' behaviour has improved significantly and weaknesses in teaching have been largely eradicated by careful selection of staff.
But attainment remains low, with "too much unsatisfactory teaching in the core subjects of mathematics and science" and a complete lack of modern foreign language teaching for 14-year-olds. Despite a determined anti-truancy drive by the school, attendance remains poor, especially in the senior years.
The report lists the results of Phoenix pupils - 11 per cent of 15-year-olds got five A* to C grades at GCSE last year, for instance - and describes them as "well below average" compared with similar schools. But "similar schools" just means those where more than 35 per cent of pupils are eligible for free school meals. At Phoenix high, 65 per cent qualify.
Mr Atkinson stressed this week that the school's intake is "massively skewed to the bottom end". Nearly half of the pupils admitted at 11 have National Foundation for Educational Research reading scores at the bottom two levels on a 10-point scale.
Boys outnumber girls two to one. And there are huge problems caused by pupil mobility: only half of the current Year 11 pupils were on the roll in Year 7; some 45 per cent have come to England in the past five years, the vast majority as refugees.
As for recruiting staff, Mr Atkinson said: "I have advertised through The TES time and time again and ended up with fields of one or two candidates."
He believes that high-quality teachers should be paid more to work in challenging schools, class sizes should be reduced to 20 and staff should only have to cover for the first day of a colleague's absence.
After four years, he said, teachers in such schools should be offered a term's sabbatical provided they signed up for a further two years.