Two new Norfolk free schools are set to open in September next year, after they were given the go-ahead by the government.

The Norwich-based Sir Isaac Newton Free School, a sixth form which its backers say will be a national beacon for maths and science and the Thetford Free School were among 102 free schools the government today approved to open in the coming years.

The Sir Isaac Newton Free School is the brainchild of Rachel de Souza, principal of Costessey's Ormiston Victory Academy and Norfolk and Norwich University Hospital chairman David Prior.

It would cater for at least 100 students aged 16 to 19 years old from across Norfolk and north Suffolk.

The curriculum would focus strongly on science and maths – with students needing to get A*s, As and Bs at GCSE in their chosen disciplines to gain a place – with other subjects also available.

The Thetford Free School, which would cater for pupils with learning difficulties or behavioural problems, was also on the government's list.

The school succeeded at the second attempt, having failed last year to get over the first hurdle.

Prime minister David Cameron said: 'Free Schools symbolise everything that is good about the revolution that we are bringing to Britain's schools.

'Choice for parents, power in the hands of teachers, discipline and rigour and high quality education in areas that are crying out for more good local schools.

'The Free Schools revolution was built on a simple idea. Open up our schools to new providers and use the competition that results to drive up standards across the system.'

But unions have criticised the concept of free schools. Chris Keates, the general secretary of teaching union NASUWT, accused the government of an 'ideological experiment'.

He said: 'Despite the spin put on this announcement by Downing Street, this is not a good news story.

'Free schools are opened at the expense of neighbouring schools, whose already diminishing budgets will be top-sliced to fund them.

'The curriculum is developed not to be broad and balanced and to meet the needs of all children and young people, but often on the basis of the personal preferences of the sponsors.'

• See tomorrow's EDP for the full story.