Letter from Lewes: Fossilised fish-hooks]: Anthony Buckeridge is 82, but the schoolboy he created remains eternally 11.

JENNINGS, the well-meaning boarding-school pupil whose exploits always bring chaos, made his first appearance in a book back in 1950. Now comes That's Jennings], the 25th novel in the series and it will doubtless be as full of brilliant surreal humour as its predecessors, which have delighted readers for nearly five decades.

Anthony Buckeridge's carefully crafted plots have made J C T Jennings a hero - the books have sold over six million copies worldwide, and have been translated into more that a dozen languages.

'I'm very proud of him, really,' says Buckeridge, a slight, quietly spoken white-haired gentleman of 82 who insists he never expected the stories to lodge in the public consciousness for so long. He was a schoolmaster himself when he invented Jennings, making up stories to read to his pupils. Jennings then became a fixture on radio's Children's Hour from 1948, making his first appearance in print two years later. Buckeridge now finds himself writing about people an amazing 70 years his junior, but he insists children don't really change, which is why - with minor updates to allow for 'outside' considerations like decimalisation and inflation - even the older books appeal to youngsters of all eras.

The first was called Jennings Goes To School. Jennings may never have come out again, but he has certainly crammed in enough drama - alongside cronies Darbishire, Venables, and the rest - to justify his long stay. Something is always lurking around the corner at Linbury Court, waiting to go wrong. And Jennings always manages to be at the centre of any particular fiasco.

He's not a malicious youngster - he just has a habit of taking logical concepts to illogical conclusions, and becoming entangled in all manner of scrapes and misunderstandings. To use Jennings's immortal vocabulary, school days seem to consist of endless 'frantic hoo- hahs' which often end with the boys exclaiming 'fossilised fish- hooks]' and the explosive Mr Wilkins finding himself in a 'supersonic bate'.

Nor do the disasters only come to the notice of the long-suffering school staff - notably Old Wilkie, the more laid-back Mr Carter, and the Archbeako (Mr Pemberton-Oakes, the headmaster). Quite often innocent members of the outside world, including police officers, famous England cricketers and Mrs Lumley at the village shop ('Home- made Cakes and Bicycles Repaired') are caught up in the chaos.

As the perpetrator of the latest example of unfathomable logic or mistaken identity, Jennings is regularly branded a 'clodpoll' by his friends. Meanwhile, Mr Wilkins, famously incapable of understanding the juvenile mind, moans that 'civilised people' wouldn't do whatever it was that had just been done.

Even lunch sees Jennings in trouble for peering at his plate through a telescope as a cheeky comment on portion size. On a school outing only Jennings could trap his head in park railings while taking a photograph - being freed only after they've been prised apart with a motorist's car jack . . . this saga also involving a fraught conversation between Mr Wilkins and the owner of the borrowed tool, a Mr Jack Carr.

Space travel holds a particular fascination for the boys - and of course it's Jennings whose head gets stuck in a dome-shaped glass case doubling as an astronaut's helmet. And only Jennings would let a pet goldfish loose in the school swimming pool in order to give it more exercise. The author's skill contrives as ever to give both the idea and its catastrophic consequences that edge of credibility.

And still Anthony Buckeridge sits at home near Lewes, Sussex - where he lives with his wife Eileen, a part-time teacher - dreaming up new exploits for his hero, pouring them out as ever in longhand before having then typed up by a woman living down the road. He still regularly hears from youngsters who enjoy his books - and also from grown-ups who read them years ago and have fished out their battered copies for their own children only to find that a casual flick through the yellowing pages has led to a full-scale wallow in nostalgia.

Buckeridge is even contemplating yet another book. Provided, as he always says, that he can keep up the standard: 'I have to think a little harder to get material - because I've used up so much. But as soon as I've got enough ideas, the writing is just as it has been for the last 40 years, really.'

Plenty of figures in children's literature - and indeed plenty of children's publications - are long-gone and forgotten. Jennings marches on. 'I'm delighted - and slightly surprised - that it's lasted as long as it has, considering that so many other things have disappeared,' is the author's modest comment.

Jennings would actually be in his fifties now. His creator has never imagined him in adult life. But he reflects and then says: 'I think he would probably be on the dole, because I can't see him being somebody who would settle down to a very serious business life or anything like that.'