Principals were asked to indicate whether learning was hindered by behaviour problems, including absenteeism, the use of alcohol or drugs, disruption in class and bullying.

Eighteen per cent of Hong Kong's principals reported that the use of drugs or alcohol was an issue - above the OECD average of 10 per cent - and 25 per cent said students were intimidated by bullying, 10 per cent above the average.

Twenty seven per cent said absenteeism was a problem, 31 per cent that disruption of classes hindered learning and 28 per cent that students lacked respect for teachers. Twenty one per cent reported that students didn't listen to teachers and 19 per cent that students didn't learn well.

But answers from principals to questionnaires that accompanied tests sat by 4,478 students from 145 schools in the summer of last year also indicated that almost all - 99 per cent - believed their students enjoyed school.

This contrasts markedly with students' responses, with 13 per cent having said school was a waste of time and 53 per cent that it didn't prepare them for adult life.

Teachers came in for even fiercer criticism from their bosses. Forty four per cent of heads said teachers didn't meet students' individual needs or encourage them to achieve their full potential, while 31 per cent said staff resisted change.

But from the students' perspective, the support they received from their maths teachers was just above the OECD average.

Sixty two per cent of students reported that their teachers showed an interest in every student's learning, and 67 per cent that they received extra help when needed.

The report also showed that in top-performing Hong Kong, Japan and Korea, maths students were most likely to be marked hard by their teachers, and thought they were no good at it. Fifty seven per cent of Hong Kong students said they were no good at maths, compared with 36 per cent of US students. Only 25 per cent of Hong Kong students said they got good marks, compared with 72 per cent of their US counterparts. The US came 28th in maths performance.

Professor Esther Ho Sui-chu, director of the Chinese University's Hong Kong Centre for International Student Assessment, which conducted the local study, called on the government to direct more support to disadvantaged communities and schools where behaviour problems, including drugs and bullying, were more prevalent.

'There should be more substantial financial and human support for them,' she said. 'But the problem of segregation is not only between schools but in the community.'

The principals' responses indicated they had very high expectations of both teachers and students, which neither were meeting, she said. This was partly cultural, and partly due to the pressure of reforms. But the study indicated relationships between teachers and students were not as bad as principals portrayed. Students recognised teachers wanted to help them, she said.

She was not surprised that teachers were resisting change. 'It is reasonable for teachers to resist, because it is too much.'

She blamed the low 'sense of belonging' among students on the pressures teachers faced, in particular the need to 'audit' everything they did. 'Teachers don't have time and space for humanistic, face-to-face contact with their students to make them feel better about school,' she said.

She believed Hong Kong could have a more positive learning culture, and still excel. 'The academic foundation is good. We have a high quality society, and high quality teenagers,' she said.