The headteacher of Oxford's top state secondary school described the job he has held for the past 22 years as "the best in English education".

Martin Roberts, who helped introduce a two-tier education system

Martin Roberts is to step down as head of Cherwell School, Marston Ferry Road, Summertown, at the end of this term.

Mr Roberts, 61, said he regretted having to retire on the brink of the introduction of the schools re-organisation, for which he campaigned over many years.

He said: "I wanted to see the new school come into existence in 2003, but there is good evidence that headteachers who stay in the job too long tend to die early.

"Being head is an absolutely fantastic job, the best job in English education.

"I enjoyed every minute of it more and more as I got older and I am leaving with considerable regret.

"Cherwell is a school with fascinating pupils from an enormously wide range of social backgrounds and abilities."

Mr Roberts, a former history teacher, who lives in Frenchay Road, Oxford, with wife Diana, stopped working in October after being diagnosed with cancer of the colon, for which he is treated at the Churchill Hospital on a daily basis.

He said his first priority in retirement was to beat the disease, then to write books.

He has already written history textbooks for GCSE and A-Level students, and plans to write a history of the Cherwell School with his predecessor as headmaster, Eric Baldwin, in time for the new school year in September 2003.

He also aims to teach people for the National Professional Qualification for headteachers.

Mr Roberts said his main achievements as headmaster were to redevelop the school buildings and preparing the way for the introduction of a two-tier education system in Oxford.

Richard Howard, principal education adviser at Oxfordshire County Council, said: "His passion for education and his commitment to what is best for young people is both infectious and influential not only in his own school but across Oxfordshire."

Mr Roberts' replacement as head is Gill Judson, currently head of a girl's school in Kent.