When Jack Linley brought out his first book Teacher, Teacher two years ago, comparisons were made with James Herriot and Gervase Phinn.

The gentle humour of Jack's fictionalised account of his first year as head of Huby primary school in the 1970s, and his gallery of oddball Yorkshire characters, also saw him compared to Heartbeat author Nicholas Rhea.

"There is a wonderful gallery of village characters, from Ruby the 20-stone school caretaker to the village carrot-growing champion George Hardisty and Miss Barrington-Huntley, pompous chairwoman of the county education committee whose peacock-feathered hat causes quite a stir," wrote a reviewer in the Evening Press.

Today, however, the most appropriate comparison is with former North Yorkshire vicar turned bestselling author Graham Taylor Just like Graham, Jack initially self-published his book. And just as in Graham's case, it has now been snapped up by a major publisher in a two-book deal worth, the former schoolmaster says, "a significant five figure sum".

Teacher, Teacher will now be published by Corgi in May - with the second book in the series, Mister Teacher, coming out as a Bantam hardback in August.

Jack - who writes under the pen name Jack Sheffield - admits he is still getting used to the glamour of being a proper author.

Teacher, Teacher hasn't even been published by Corgi in this country yet, but it has already been translated into German - and there is interest from five publishers in the US.

There is even - whisper it quietly - "significant interest" from TV.

So excited are his UK publishers, Transworld, that they threw him a champagne reception at their offices in London.

He went with his agent. "There was champagne and Bucks Fizz and I arrived wondering who this reception was for," he says. "It was for me!"

There is little wonder the publishing world is so excited.

Teacher, Teacher brings to life as never before the lost world of the small Yorkshire village school in the 1970s.

Jack, who now lives in York, was head teacher at Huby for six years from 1977 to 1983, before going on to be head of a larger school also near York, and then a lecturer in education at Leeds University.

Teacher, Teacher is set at a fictional school in a fictional village - Ragley-on-the-Forest near York - which is an amalgam of Huby, Sutton-on-the-Forest and Easingwold, with a healthy dose of imagination thrown in.

It is full of colourful Yorkshire characters - including a comic villain, local pig-farmer Stan Coe, who has more than a touch of Claude Greengrass about him.

"He's a boorish bully of a pig-farmer who always gets his come-uppance," says Jack, before adding hastily: "He's not based on anyone I knew."

The central character is Jack Linley's alter ego Jack Sheffield, who arrives to take over the school in 1977.

He is a gentle, unassuming young man - the sort lots of women would love to mother, Jack admits - who begins to record the day-to-day goings on at the school in his "alternative school logbook".

Jack Linley the author (and former headteacher) proves to have a wonderful recall, as well as a great eye and ear for detailed observation.

There is also romance in the air, with the fictional Jack falling for PE teacher Beth Henderson - a "young, blonde, 5 foot 6 inch, slim and athletic teacher," the real Jack says.

The big question, for much of the book, is whether Beth will fall for him.

So what made Jack think of the name Sheffield for his alter ego?

As a young boy at primary school in Leeds, he remembers his teacher reading White Fang, by Jack London, he says.

"I told the teacher one day, I would like to write a book'. And he said when you do, you can call yourself Jack Leeds, or Jack Sheffield'".

And so he did.

Getting into print, he admits, is an ambition fulfilled. And in an odd sort of way, he owes it all to Jimmy Savile.

As a young man, he had always wanted to be a sports reporter.

He played rugby for Yorkshire schoolboys, and had an interview at Sheffield University to study English. They were all set to offer him a place on the course - and in the university's rugby team - when they realised he didn't have Latin O-Level.

He was rejected. Disconsolately, he returned to Leeds by train - and leaving the station bumped into Savile.

"He had broken down in his bubble car," Jack recalls.

Jack helped him push the car to safety, and the DJ invited him for coffee.

Jack told him that, having failed to get a place at Sheffield, he was tossing up whether to join the army, or become a policeman or a teacher.

"And he said: The best job for you is a teacher'," Jack recalls.

So he came to York's St John College to train as a teacher: and the rest, as they say, is history.