Jonathan Smith has combined his teaching and writing talents to produce that rare thing, a page-turner about education. His latest book, The Learning Game, includes lots of self-revelation, a sprinkling of advice, pot-shots at such things as coursework and “the parent from hell”, and, running like a thread through the book, a huge emphasis on the human qualities of warmth, respect, energy and humour that go into making good things happen in schools.

So it is surprising to meet a man who seems altogether more angular - tall and craggy, impeccably dressed and unfailingly courteous, yet correct of manner and with a faint air of wariness about him.

This may be due to the prospect of having one of his lessons observed by The TES - something, he says, he could hardly refuse, given the book that he’s written, but which had him awake at dawn feeling apprehensive. “You do rather lose a sense of your own territory when someone else is in the room.”

But all passes smoothly. At mid-morning a tiny A-level class of seven filters into his classroom, in the English department of Tonbridge school, Kent. Somewhere outside are the shaved playing fields and Gothic turrets of a traditional boys’ independent school, but the immediate view is of a gloomy slated roof and brick wall, which makes the posters, poems and pictures with which Mr Smith decorates his room - his book devotes four pages to the importance of this. “I love my classroom,” he writes. “I could go to sleep in it. Some of my pupils do” - all the more welcome. The boys hand in their coursework, then settle to a critical examination of two pages of a joint AudenIsherwood play underneath a poster of one of Smith’s previous pupils at Tonbridge, the prize-winning author Vikram Seth, who inscribed a copy of his massive novel, A Suitable Boy, “To Jonathan, who always encouraged me to write briefly”.

Smith teases out the pupils’ reflections on the text in the manner of teachers everywhere, but interrupts them with wide-ranging asides covering the political climate of the Thirties, from what is meant by “Brechtian technique” to the mystery of Auden’s missing seven weeks in Spain during the Spanish civil war. The boys listen with polite attentiveness, filing it all away, he hopes, to inform their future lives.

In his book Mr Smith says that teachers have a duty to tell their pupils things. “And for me that was one of the most important sentences in the book. Teachers telling you things, teachers listening to pupils and responding to them, that whole-class electricity - to my mind that is the absolute crux of it, and if someone says, ‘What a dinosaur, what an extraordinary thing to say in the year 2000’, well then so be it.”

Another deeply held belief is that today’s relentless burden of coursework puts students under stress, and constrains good teachers. “The more you have these short-term aims, the less risk-taking and exciting teaching you’re going to have because everyone’s always going to be focusing down on the exam, rather than having one eye on the exam and the other on the stars.”

Mr Smith knows that he will attract flak for pontificating about teaching from an independent school such as Tonbridge, where he has spent almost all of his career. “But as I say in the book, everybody in my family, everybody in my wife’s family, has been involved in state education. I’m not, but I’m still a full-time, six-days-a-week teacher, who’s spent his life teaching. If people wan to say, ‘You’re in an independent school therefore I’m pulling the plug on everything you say’, all I’d say is: read the book. Are there things in there that ring true, and that are enduring?” He is confident that there are, not least because his brother-in-law, who has spent his life teaching in comprehensives, rang him up the night before the interview to tell him he’s hit all the right buttons.

He wrote The Learning Game, he says, because he’d got to the stage of life of being “the poor old bloke in the corner” that younger teachers looked at with pity. He had been planning to write it when he’d given up teaching. “But then I wanted to do it while I could still touch all the tension and excitement and irritability that makes up an average professional day.” Then, when he starting writing, “it just poured out of me. I wasn’t expecting it to take me over like it did, but it became much more personal, much more of a journey, and I wrote it with the same kind of excitement that you’d write a novel.”

That excitement is familiar to someone who has written five novels and “between 15 and 20” radio plays, and it seems certain that his long stay at Tonbridge has been nothing at all to do with inertia and everything to do with finding a life that has suited his interests and talents.

In term-time he lives a rounded school life, coaching sports and producing school plays. He ran the English department for 17 years, until he stepped down five years ago. In the holidays he has been able to retreat to his house in the school grounds - where he and his teacher wife brought up their son, who went to Tonbridge and is now a Kent county cricketer, and their daughter, who went to a maintained school and now works in publishing - and assume the life of a writer.

In 1975, he published Wilfred and Eileen, a love story set during the First World War. “A pupil told me about his grandparents, and then gave me their diaries,” on which it was based.This was followed by four other novels, the most recent of which, Summer in February, was published in 1996. In the early 1980s Wilfred and Eileen was made into a television series, and among Mr Smith’s radio dramas has been an eight-play series, The Head Man (which was broadcast in the early 1990s) about the political and psychological life of a headmaster.

“Being a radio dramatist actually suits being a teacher because you can write a radio play in the holidays. The trouble with a novel is that when you’re doing it holiday to holiday, it can die on you a bit, so you have to spend the first week of the holidays getting it back.”

He has just finished a television screenplay which looks as if it might be commissioned, and has plenty of other ideas to act upon. Some time in the near future he will step down from Tonbridge, knowing he will miss the buzz of school life but looking forward to the different challenges of life as a full-time writer.

Chapter and verse 1942 Born in Gloucestershire. His parents, as well as his aunts and uncles, are teachers 1947 Attends Berkeley county primary, where both his parents have previously taught 1949 Attends Patchway Church of England primary school, Bristol, where his father is headteacher 1952 Attends Christ College, Brecon, a small independent boarding school 1960-64 Reads English at St John’s college, Cambridge, and stays on for a year of research. In the holidays, teaches at Patchway secondary school and later marries the headteacher’s daughter, Gillian Scarborough 1964 Takes up first teaching job at Loretto school, near Edinburgh 1967 Moves to Tonbridge school 1974 Teaches at Melbourne grammar school in Australia on a one-year exchange. Returns to lecture in Australia in 1982 and 1996 1975 Writes Wilfred and Eileen, the first of five novels 1996 Latest novel, Summer in February, is published