After a spell of writer’s block, Alan Bennett has made a stunning return with his new play The History Boys. He described its creation at the National Theatre ahead of a tour that reaches Norfolk this month.

What is the point of going to school?

It is a question that is asked by just about every adolescent at some point, but rarely can the issue have been explored so delicately or extensively as in Alan Bennett's new play.

If you need reminding why Bennett is widely deemed a national treasure then a visit to see The History Boys at Norwich Theatre Royal this month should suffice.

It is a wonderfully funny and intelligent look at an anarchic group of sixth-form boys in a Sheffield school in the mid-1980s, whose chief interests are sex and being educated well enough to get through their Oxbridge entrance exams.

Coaxing them along is Hector, an eccentric English teacher with old-fashioned notions about learning simply for the love of acquiring knowledge, rather than to pass exams: an approach that clashes sharply with that of a results-driven headmaster who views the world in league tables and is suspicious of anything he cannot quantify.

Bennett's disdain for the press is well known - it is thought to stem from the red-tops tabloids' treatment of his friend Russell Harty, who died of an Aids-related illness - but he overcame it sufficiently to talk to regional newspapers from the areas in which The History Boys will be performed.

“I had always wanted to write something about a charismatic schoolmaster; that went back quite a long way,” he explained.

“Someone at Shrewsbury School once told me about a teacher they had had. He taught Paul Foot and a lot of the Private Eye lot and he had this method getting the boys to learn snatches of poetry, which he called 'spells'.

“There was a circle on the floor and a stool in the middle, and they would stand and declaim the poetry. That was the example of the kind of schoolmaster I wanted to write about.”

Richard Griffiths played Hector in the run at the National's Lyttelton Theatre, winning an Olivier Award for Best Actor in the process, but acclaimed Shakespearean actor Desmond Barrit replaces him on tour.

He will be joined on stage at the Theatre Royal by Bruce Alexander as the headmaster, Diane Fletcher as Mrs Lintott and Tobias Menzies as Irwin.

Bennett, 71, explained that of the eight young actors who played the students in the original National Theatre production, only one had stayed in education after the age of 16. As a result, they had faced a steep learning curve, but this had its benefits.

“A lot of the stuff in the play was totally mysterious to them, and the people mentioned in the play were mysterious too. All were amazed that there were laughs in what they took to be straight dialogue.

“A lot of the first two weeks [of rehearsals] consisted of telling them who Thomas Hardy or Wilfred Owen were and telling them about the first war and the second war. In the course of that they talked about their own experiences.

“They found my ignorance of some things ludicrous. The good thing was that they could say what they didn't know without anyone thinking they were stupid.”

Much of the development came in rehearsal, a product of a hurried schedule as much as a deliberate approach on the part of director Nicholas Hytner. Bennett's typically self-deprecating description makes it all the more impressive that such a life-affirming piece of work arose from such conditions.

“I sent the first draft to Nick in October 2003 thinking we would work on it a year later. They wanted it in March,” he explained.

“A lot of the work was done in rehearsal with the boys at the National Theatre Studio. Some of it was finding out what they can do. Jamie Parker plays piano very well. He never said that in auditions or rehearsal, and it was only when we got to the scene and had someone come in to play piano that he said 'I think I could do that'. And he played it perfectly.

“Nick [Hytner] was doing a programme called Private Passions, a kind of superior Desert Island Discs, and I was listening to this. One of the records he played was Ella Fitzgerald singing Bewitched. I thought it would be wonderful if it were sung by a boy with an unbroken voice.

“All these things were part of the sort of mess out of which the play came.”

The musical interludes are important to the play's success, giving voice to the students' creativity. The Ella Fitzgerald number is sung by the character Posner, a sensitive Jewish boy who has a crush on a fellow schoolboy. Shades of the author seem to inform this character.

Over the years, Bennett has kept his private life distinctly private.

In response to Ian McKellen asking whether he was gay, he replied that the question was akin to asking a man crawling across a desert which brand of mineral water he would prefer. Recently, however, he outed himself in an essay in the London Review of Books, in which he described being a victim of a “queer-bashing” attack in Italy with his partner, the journalist Rupert Thomas.

“Obviously I don't have children, I have never had to face the problem of putting a child into the right school,” he said.

“I think it's true that a teacher like Hector would be an asset to any school but would find it hard to fit into the norms of education today.

“I first heard of teachers like that when I was in the army, from boys who had been to public school, but never had one myself.”

His own schooldays in Leeds were “quite dull”, and as for his teenage self, he was “awful”.

“I was very late growing up. I was 16 and my voice hadn't broken. I was this innocent-seeming boy but also quite prurient. A very unattractive combination. I was a clever boy, but I was just bored until I was 16 or 17.”

Education has been an occasional theme in Bennett's work. He said that the production could be seen as a companion piece to his 1968 play Forty Years On, the success of which led him to concentrate purely on writing rather than performing his own material.

“I don't miss performing. When I come down here and see the curtain go up, I think 'Thank God it's not me'.

“I'm still surprised how little stage-fright they have got. They can be talking right up to the moment the curtain goes up. I would be petrified.”

His experience on the stage remains useful, as it seems to have shaped his writing method.

“Anybody who saw me write would think I was insane. I shut [the world] out and go around the room and say lines. I have always done that. I couldn't work in a room in which anyone else was there.

“In a sense it's useful having been an actor because you adjust it and smooth it down so that it's easy to say. I think some writers who haven't performed don't realise that.”

But he wouldn't be Alan Bennett if he didn't have a degree of self-doubt about his work.

In the past he has described writing as “a deplorable profession”, saying that “we can justly be accused of exploiting people, because that's exactly what writers do”. It appears he hasn't changed his opinion.

“Philip Roth said what a seedy profession it was to write. He was at his father's deathbed and he was watching this knowing that he would write about it. That's kind of cannibalistic. I imagine every writer does that. But other things you pick up because nobody else wants them.

“You don't know what's going to be useful. I used to note everything down but I got such piles of paperwork. What's useful if you have notebooks and notes of things is that it helps you to avoid the terrible moment where you have a blank sheet of paper.”

In 2001, Bennett was particularly afflicted by writer's block, to the extent that he told an audience in London that Hytner had asked him to write a piece for the National Theatre but he had been unable even to begin the task. “I would love to be able to write something, but the very asking makes it impossible,” he said then.

It emerged last weekend that he was treated for colon cancer in 1997. His new autobiography, Telling Stories, reveals that surgeons removed a "rock bun" sized tumour, and he was given a one in five chance of survival at the time.

Thankfully he recovered and regained inspiration, and some - The History Boys is that rare thing, a truly uplifting piece of theatre. He is wary of the idea that there is anything as leaden as a “message” to it, however, despite the fact that it forms a timely attack on the results-driven culture of modern education.

“I didn't specifically include things because they were topical or relevant, it's only what came out.

“You can't write a play like that. It has to come out of the characters. If you write it around the characters, they find things they want to say. They may be things that you want to say,” he added with a dry smile.

Throughout his career, from the days of Beyond the Fringe with Peter Cook, Dudley Moore and Jonathan Miller, to the poignant monologues of Talking Heads, Bennett has never seemed the gregarious type. So it was interesting to hear him say: “The best thing is people coming up to you in the street and saying they have had a very good time. I never thought it would be a family show but it is. Presumably, the children get something different out of it from the parents and grandparents, but they do get something out of it. We get children younger than 16 and they have a good time, and I think that's because it has a lot of bad language in it!”

It appears that this relatively outgoing mood - talking to the press, embracing public recognition in the street, discussing his sexuality - is linked to the creation of such a fine piece of work.

It played to sell-out audiences at the National Theatre for months on end and picked up the Evening Standard, Critic's Circle and Olivier awards for best play.

When he collected the latter to a standing ovation, he said: “Theatre is really doing, not what you've done, and the thing we're doing, The History Boys, has given me more pleasure than anything I can remember.”

It is a sentiment shared by the thousands who have filled the National Theatre, and it's hard to imagine that the Norwich audiences will disagree.

t The History Boys is at Norwich Theatre Royal from October 25 to 29. Tickets are priced from £4 to £20. Call the box office on 01603 630000 or visit www.theatreroyalnorwich.co.uk