In the third part of a series looking at recently-published accounts of academy schools, education correspondent Martin George looks at the financial challenges some are facing.

Thetford Academy is planning to make £1.5m in savings in the current financial year, on top of £570,000 in 2013-14.

The need to make savings comes because governors identified 'the risk of a significant budget gap over the medium term' that governors identified.

Its accounts show the school, which had an income of £7.99m last year, had a deficit of £338,000 - up from £75,000 the previous year.

The academy formally transferred from its previous sponsors to the Inspiration Trust in September 2014.

The Inspiration Trust's accounts showed its flagship maths and science free school, the Sir Isaac Newton Sixth Form, had a £100,481 deficit, blamed on potential students being deterred by delays securing a permanent location.

Its original application form was based on having 220 students in its first year, but in January 2014 it had 69. The accounts said the new intake for 2014-15 was double that of the first year, 'albeit still some way short of capacity'.

Hethersett Academy, which joined Inspiration in November 2013, had a deficit of £35,527, blamed on a falling school roll caused by the period it was in special measures.

Inspiration's accounts said the remedy for Sir Isaac was to 'establish a first-class reputation and increase the roll towards capacity', while staffing and curriculum changes at Hethersett had been made to revive the reputation of the school.

Great Yarmouth Primary Academy, Norwich Primary Academy, Cromer Academy and the Jane Austen College reported surpluses.

An Inspiration Trust spokesman said: 'The accounts show the Inspiration Trust is in good financial health and, as clearly set out on page 39 of the accounts, we have plans in place to deal with deficits, which have mainly been inherited from schools the trust took over or are the result of planning delays impacting recruitment. We always put our pupils and their education first in any plans to deal with deficits.'

The Nicholas Hamond Academy in Swaffham, sponsored by the Academy Transformation Trust (ATT) since November 2012, had a £267,000 deficit.

ATT managing director Joyce Hodgetts said the school joined with a deficit budget, and ATT knew that, because of its investment and new resources, 'the academy's budget would remain a deficit in the short term but would achieve a positive budget in the longer term'.

She said ATT has invested £267,000 of revenue funds into the school by the end of 2013-14, and it received equal resourcing to any other ATT school, and there were already improvements in results, pupil numbers and the buildings.

She added: 'Over the time, if the current growth in pupils attending the academy continues, this alone will have a significant and positive effect on its budget.'

Last week's coverage highlighted financial problems faced by City Academy Norwich, which is sponsored by the Transforming Education in Norfolk (TEN) Group.

Its accounts report a £461,000 deficit, which a spokesman said was largely due to having to repay two over-paid government grants of £479,000 and £317,000. He added that, excluding the impact of depreciation, the in-year position was £1,000 surplus.

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