Pupils know best. This was the message on a poster distributed by the European School Students Union in advance of their Pisa conference last month.

The theme of the conference was “quality in education” and the fuse was lit by a Finnish headteacher who made her own bold claim for “knowing best”. After 22 years of much water and many bridges she could say with conviction that she knew her school. This brought a swift rejoinder from a 16-year-old Dutch delegate. Politely borrowing the mike he said: “I have sat in classrooms six periods a day for 30 weeks a year for five years and, with respect, I see things you could never see. These five years are my life in school. They are my one chance.”

The beauty of it is that both are right. Who could argue with the head? Who could deny the validity of the student’s experience? If we are serious about evaluating quality and standards in schools this dialogue is at the heart of the issue.

The danger lies in the eitheror. It lies in the dogmatic judgments, whether from heads, students or inspectors. Each brings a lens, a vantage point from which to view the school. The headteacher takes a bird’s eye view while the student sees it from the worm’s eye. The inspector brings an outsider’s view, a third eye.

It is the juxtaposition of these viewpoints which brings new ways of seeing. The willingness to treat all of those perspectives with concern for evidence and openness to challenge is in itself a model of educational process. A culture of school improvement is one which nourishes the quality of that dialogue.

The most rewarding experiences for me in 1998 have been to visit schools as the outsider, as “critical friend”, to sit round the table with heads, teachers and pupils openly exploring the quality of learning and teaching in their schools.

There are two ground rules for such a discussion. One, leave status and position at the door. Two, seek first to understand before seeking to be understood. In every instance, headteachers and teachers prescient enough to engage in the exercise in the first place have found it an enriching experience.

Evaluating Quality in School Education is the title of the European project involving 101 schools in 18 countries. Each of these schools has used the same approach - a self-evaluation profile of the school, completed only after a rigorous process involving children, teachers, heads, parents and governing bodies. They come to the exercise as equal partners and with an equal right to be heard.

At a recent review of the project in Brussels attended by policy people from the 18 participating countries, responses to this approach ranged from the positive to the evangelical. For many of the countries present it had opened windows and dispelled their darkest foreboding. It had illustrated how organisations can learn from their members. It had, said one ministerial adviser, reinvigorated their schools.

For other countries it had reinforced and validated what they were already doing. The UK, well represented with nine schools, provided some of the most glittering examples of what can happen when schools are open to learning and have the tools for self-evaluation.

For example, in Sandringham School, St Albans, they are exploring the theme of “time as a resource for learning”. The interest in this issue was prompted by a difference in opinion among pupils, teachers and management about how time for learning (as opposed to time for teaching) was used.

To find harder evidence, governors have been shadowing and interviewing individual children. Senior pupils sat at the back of classrooms with observation schedules. Younger ones armed with tape recorders interviewed their older peers about “quality time”, in different learning contexts. Students in groups discussed the yardsticks of effective learning and made suggestions for more effective teaching. Video and photo evaluation was used to provide a focus for dialogue.

Nothing soft or wish-washy here. No cant and no dogma. Just deep digging, challenging some of the most fundamental conventions and assumptions as to how learning comes about. The evidence, shared and discussed with everyone - governors, parents, teachers and children - has been the source of development planning and the wellspring of motivation for improving quality and raising standards.

Evaluating quality cannot be a one-off exercise. It does not come about simply through audit or inspections. It is a process through which schools get to know themselves, use evidence, build on strengths and attend to the warts. In this process pupils - both primary and secondary - have a vital role.

In a recent newspaper article I advocated that students ask the question:

“Why are you teaching me this today?”. Included in the many letters I received was a poster from a primary school which, the head said, hung in every classroom, library and corridor. It bears the words “What did I learn in school today?” It is a vital question. If we do not stimulate that inquiring subversive intellect when children are young they are likely, as adults, simply to accept as truth what they read in the Daily Mail.

Among my most prized of those letters is a collection from a German school in Paderborn. Each member of a sixth-year class had written a letter in excellent, and sometimes idiosyncratic, English. “It is better to learn practical thinking than to learn just fixed facts and knowledge which you forget immediately when your school career is over.” “I wish you a lot of power to keep on fighting against old-aged teaching methods.” “We learn just the lowest knowledge state, so we have to change many things to guarantee thinking-centred schools of the next generation.”

“The thinking school, the learning nation”, is the new slogan for Singapore schools. Their government announced two weeks ago that they would put in place measures to discourage the relentless pursuit of A grades. They promised a cut in curriculum content of up to 30 per cent. They promised more project work, more independent and collaborative inquiry, more time for music, drama and the arts. They are introducing open-book exams which encourage thinking and discovery rather than regurgitation of inert ideas.

Thinking schools require thinking students who are not merely consumers but producers. They are potentially the most powerful single source for rigorous quality assurance and continuous school improvement.

John MacBeath is director of the Quality in Education centre at Strathclyde University