For some of Oxford’s historic colleges, 50 years is hardly a time span worth emptying the wine cellar to celebrate.

But half a century is a long time in the existence of an Oxford state school.

Being able to mark a 50th birthday while on the crest of a wave of success, as a school recognised nationally for all the right reasons, is a rarity indeed in this city.

Next week, Cherwell School will be able to host such a happy golden jubilee, having grown from a small school hardly known outside the city to one Oxfordshire’s largest and best.

Nor can many state secondary schools in the city claim such longevity.

Since Cherwell School opened its doors in September 1963, with just 323 pupils, 12 teachers, one full-time secretary, a part-time administrative assistant and a caretaker, three schools have closed (Milham Ford, Cowley St John and Redefield).

Three more, perhaps with little reluctance to shake off their pasts, have changed their names (The Oxford Academy from Peers; Oxford Spires from Oxford School; and St Gregory the Great from St Augustine’s).

Only two, Cherwell and Cheney, have continued to evolve on the same site, keeping their original names.

Cherwell will be hosting a jubilee festival at the school on Marston Ferry Road on Saturday, July 13, for pupils, parents, alumni and the local community, with tours, speeches, performances and a funfair.

But the anniversary is also being marked with the publication of a new book The Cherwell School, The First Fifty Years (Shire Publications £7.99).

Its author, Martin Roberts, is doubly well qualified to chart the remarkable evolution of the school, which today has more than 1,800 pupils, 139 teachers, 74 support staff, 29 administrative staff and six caretakers, plus a premises manager.

Mr Roberts, 71, of Frenchay Road, Oxford, was head of the school from 1981 to 2002. And in addition to writing an earlier book on Cherwell’s 40th anniversary, he also penned a book marking the end of Oxford’s first comprehensive school, Peers, in 2008, closed to be replaced by Oxford’s first academy.

That book charted the transformation of Peers from a vibrant place of education to a failed school in an educational tragedy intrinsically linked to the peculiarities of Oxford’s social make-up.

The story of Cherwell, in many ways, could hardly be more different, although social make-up and educational reforms have also played their part here too.

With its pupils regularly achieving some of the highest grades in the country, many would agree with Mr Roberts’s assertion that it is widely viewed as the best state school in Oxford.

Heavily oversubscribed every year, it is in the Ofsted ‘outstanding’ category, becoming in 2013 one of the three Oxfordshire schools named as ‘teaching schools’, to share expertise across the county.

But when the school gates first opened at Cherwell as a secondary modern to cater for the 75 per cent of the local population who failed the 11-plus, such success could not be imagined.

North Oxford, then as now, had a high proportion of upper middle class families, being home to many Oxford University academics and research staff. But those who chose not to send their children to independent schools would look to Oxford’s two grammar schools — Milham Ford in Marston for girls, and Oxford for boys.

Most pupils in its early years left the Cherwell at 15 without having taken any examinations.

When Mr Roberts, a Merton College history graduate who had taught at Leeds Grammar School, became headteacher at the age of 39, the school continued to face testing times.

“Cherwell was a hotch-potch of poorly-built buildings, some in a bad state of repair, with structural beams in the main teaching block rotting, and roofs leaking. Four temporary classrooms catered for extra pupil numbers,” he recalls.

“In the early 1980s there were four main challenges facing the school: falling school rolls, funding cuts, the state of the buildings and improving the school’s reputation.”

With Oxfordshire LEA agreeing that six Oxford schools had to be reduced to five, Mr Roberts frankly admits that he feared his new school might be the one selected for closure.

Recognising entry to top universities was the important criterion in North Oxford for judging a school, he gave priority to improving A-level results, rarely appointing any new teacher who could not teach A-level confidently. By 1987 it was achieving the best exam results in the city.

He also arrived to find uniform regulations at Cherwell varied and casually observed. Personally seeing no point in uniform, he nevertheless fretted parents might think poorly of a non-uniform school. After 51 per cent of parents voted in favour, uniforms were abolished in 1986 and it has remained one of England’s dwindling number of non-uniform schools. But then he readily admits that there are many things that make Cherwell unique.

“Its intake is skewed upwards because of its geographical position. It has far more youngsters who have above-average ability. Once we had won the confidence of the local community, the school went from strength to strength.

“I used to say I have the best education job in England. The school was comprehensive, but with an unusual proportion of lively pupils who responded to good teaching.”

He tells the story of one new teacher’s early experience of parents’ evening. She found herself describing a youngster’s progress in science to a very interested parent, who, she was to discover, happened to have won a Nobel Prize for biology.

“But there is a major challenge for Cherwell. It is in the heart of this extraordinarily advantaged community but there are pockets of disadvantage too, in Cutteslowe and Wolvercote. It is important to make sure that Cherwell is viewed as the school for them too.”

He is delighted that Cherwell is now formally linked to Cutteslowe Primary School.

However, the greatest upheaval in the school’s history occurred only a decade ago, when it changed from an upper school to a secondary school, for children aged 11 to 18. This resulted from the reorganisation of the city’s schools from three to two tiers, with the closure of middle schools.

The policy was to face fierce opposition. Cherwell was plunged into the centre of the dispute, with the outcome having major consequences. The school ended up taking over the Frideswide site across Marston Ferry Road, to almost double the school in size.

On April 1, 2012, Cherwell freed itself from LEA control, when it became an academy school, now managed by The Cherwell School Academy Trust.

With Oxford having seen good schools become poor in the past and the all too likely prospect of further central government fiddling with school systems and structures, can such success be sustained long into the future?

Mr Roberts will be heading for the jubilee festival in confident mood, where he will pay tribute to the heads that have followed him, including Jill Judson and the present headteacher Paul James.

“The school’s roots are so entrenched that when another 50 years have passed, unless some unforeseeable catastrophe occurs, a famous school will be thriving.”