One day last year I was sitting in an office at Seven Kings high school in Ilford with the school’s headteacher, Sir Alan Steer. He repeated something he had said a few times already in the months since I had begun following selected staff and pupils for a book about the school. Would people really want to read about these youngsters? After all, he said, they were just ordinary kids.

It was a moment of revelation for me. I responded that on the contrary, I found them extraordinary - individually and collectively. And this, for me, is key to what makes Seven Kings special. Like most good schools, its pupils are its proudest assets. Take Perin, for example, an intelligent, unassuming young man whose parents came here from Uganda in the 1970s. His clear vision of his own bright future is pure gold dust. Or Kessie, who came from Ghana at the age of 10 and whose capacity for hard work is astonishing. For Kessie, breaktimes, lunchtimes, even registration periods, are opportunities to study.

These two are among the school’s star pupils, of course. But they are far from exceptional. In fact their qualities seem to me a distillation of all that is good about Seven Kings. It is serious yet friendly, it is rarely flashy or loud. It has a quiet sense of purpose and direction.

I went along in the spring of 2004 with a half-formed idea for a book.

Although I had been writing about education on and off for more than 15 years, I had never spent more than a few hours in any single school, and I wanted to remedy that. I wanted to know what happened on an ordinary day between the walls of an ordinary comprehensive. I wanted to sit in the backs of classrooms, to follow pupils and staff out on to the playing fields, into the canteen and the sixth-form block. I wanted to follow them home at the end of the day. If Seven Kings was a good school - and it certainly was - what was it that made it so good?

There are certain fixed points, of course. The students are one. Eight out of 10 pupils at Seven Kings have their ethnic origins in the Asian subcontinent, and only a small minority are white. There is a tremendous sense among many of them that their families are on the move, socially rather than geographically. Yet there are things happening inside the school, too, that make it what it is. Fifteen years ago its GCSE results were just below the national average, now they are among the best in the country. The school’s intake is non-selective and its pupils’ prior attainments close to the local and national norm, yet it is consistently listed among the top 10 for value added. So what is it all about? Has Seven Kings high school discovered some magic dust which it has scattered among its pupils? Unsurprisingly, the reality is much more prosaic.

The magic of Seven Kings is, like its pupils, much more low-key, much more down-to-earth. As Sir Alan - leader of the Government appointed task force on behaviour - is fond of saying, success here is not about knowing what to do, but about doing what you know. Always.

Nothing is ever left to chance. A thousand little ingredients, mixed every day without fail, make up the recipe for this school’s powerful brew. It starts at the school gate. Every day as the pupils cross this frontier they are greeted by a member of the senior management team, reinforcing the message that school is another country. “Morning, Simon. Tuck that shirt in please... How’s your brother getting on, Rahul?” The message that school has certain norms, certain standards, is constantly reinforced. Little daily reminders of the uniform policy, messages to parents that boys must shave their chins rather than their heads. There is the sense that within its walls sits a single, coherent entity where the aberrant must learn to comply. It might not suit every school, but it works here.

This single-mindedness goes beyond such petty daily frictions as uniform policy. High standards are expected of all, children and adults. At the start of the year the staff are handed a new teaching and learning policy:

“Teachers must have a seating plan for every class. Lessons must last the full duration and students must not be dismissed early. Punctuality is essential for staff and students.” Few people could accuse Seven Kings of woolly-minded liberalism.

The school knows what it is, it knows where it is going and it knows its clientele. The parents of these pupils have academic aspirations for their children. They would not welcome the vocational courses in beauty which are offered at the local college, and so the curriculum focuses mainly on traditional subjects - though there is a special IT GNVQ class for pupils at risk of not getting the regulation five A*-Cs.

Yet there is more - much more - than a straightforwardly authoritarian structure. One of the things that impressed me most is the way in which the staff, from the head down to the newest NQT, think constantly about what they are doing. There is always room for improvement through analysis of the school’s needs. Sir Alan talked about how a head’s job is several parts guilt: he would read an article in the paper and think, we should be doing that. In this way he introduced regular interviews for all students about their progress. Debbie Adams, an English NQT, has set up a lunchtime group in which older students act as mentors to younger ones.

But the best thing about Seven Kings, for me, is its humanity. The head of sixth form was in tears when she said goodbye to her charges for the last time, and so were many of them. Doug Harrison, the head of pastoral support and also a year head, not only knows the names of all the students in his year group but always has some personal knowledge of each one which informs his chat when he meets them around the school. There is much about Seven Kings that could have come from a textbook on how to run a good school. But that human touch is something no amount of research, no DfES circular, can distil or distribute. That, to me, is real magic.

Seven Kings: How it feels to be a teenager, by Fran Abrams. Atlantic Books, pound;9.99