Abbeyfield School in Chippenham achieved the best GCSE maths results of all the local authority maintained schools in Wiltshire.
Its maths department saw 83 per cent of students achieving an A*-C grade in the subject in GCSE in 2012 – and 90 per cent of boys.
This compares with an average of 69 per cent for state-funded schools.
Headteacher David Nicholson said: “We are very pleased. This is due to very strong leadership and a belief that every child can get the grade.”
It is the sixth consecutive year that Abbeyfield achieved a record set of GCSE results, with 64 per cent of all students achieving the Government’s benchmark of five or more A* to C grades including English and maths. This puts the school in 14th place out of the 37 schools in Wiltshire.
Mr Nicholson said: “We’ve gone from 48 per cent in 2006 to 64 per cent in 2012. It is a testament to the hard work of all our teachers.”
Abbeyfield came in 23rd place for A-levels.
Staff at nearby Hardenhuish had reason to celebrate as it came eighth of all schools in Wiltshire for its A-level results.
Headteacher Jan Hatherell said: “At A-level, Hardenhuish’s record means that our students have the pick of university courses at the end of two years of study.
“This is also confirmed by the Sutton Trust research, which puts Hardenhuish in the top 50 comprehensives in the country for access to Oxford and Cambridge.”
Hardenhuish saw 60 per cent of pupils gaining five or more A* to C grades, coming in 20th place out of Wiltshire’s 37 schools.
Mrs Hatherell said more than 20 of the school’s GCSE pupils were awaiting the results of a judicial review into their English language grades. The school believes they should have been given a pass grade.
In terms of the value added measure at GCSE, which shows how well a school has helped its pupils progress since arrival from primary school, Hardenhuish was the highest performing school in Chippenham and one of the best comprehensives in Wiltshire.
Mrs Hatherell said this showed how much the school had helped pupils of varying abilities.