The sponsor of a flagship free school has said its future is secure, despite concerns consistently raised by its board about its deficit and student numbers.

The Sir Isaac Newton Sixth Form, which opened in 2013 and is sponsored by the Inspiration Trust, had a £100,000 deficit in its first year.

It is based at the former Bethel Street fire station in Norwich, and the minutes of the trust's board meetings, obtained under the Freedom of Information Act, show concerns have been raised since it first opened.

In its first year, it recruited less than a third of the possible 220 students, and in October 2013 the board said student recruitment levels were 'currently disappointing and needed to improve', but Inspiration Trust chairman Theodore Agnew spoke of his 'confidence in the long-term viability of the school'.

In March 2014, the board sought written reassurance from the Education Funding Agency that Sir Isaac's forecast deficit and negative closing reserves would not lead to a qualification being applied to overall accounts of the trust. No such qualification was made.

Ofsted rated the sixth form 'good' in all areas in its second year, but the board continued to have concerns about its finances.

In December 2014, it discussed the possibility of loan from the Department for Education to address the deficit, although a spokesman said he thought this did not happen.

The February 2015 board minutes said the sixth form needed 270 students to break even. It had 172.

The board decided to look into the possibility of running Sir Isaac and the Jane Austen College, another Inspiration Trust free school in the city, as a 'single entity'. A spokesman said this was not pursued.

Sir Isaac's financial position was raised again May, when minutes said 'plans to address the projected deficit at Sir Isaac Newton were noted', but gave no further details.

A spokesman for the Inspiration Trust said: 'There is absolutely no risk of Sir Isaac closing. It has always worked closely with Jane Austen but the two are not merging.

'Sir Isaac Newton Sixth Form had a fantastic first set of A-level results this summer, including a Cambridge place and overall grades in several subjects well above the national averages, and we have just had two very busy open evenings for students starting next September.'

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