A headteacher has apologised to parents for disruption at his school after staff shortages meant class sizes increased.

Eastern Daily Press: The Atrium at North Walsham High School. The school has undergone several staffing changes. PHOTO: ANTONY KELLYThe Atrium at North Walsham High School. The school has undergone several staffing changes. PHOTO: ANTONY KELLY (Image: � ARCHANT NORFOLK 2012)

Several teachers at North Walsham High have been suspended, left or gone off sick this term, prompting the largest union at the school, the NASUWT, to go to the board of governors.

But headteacher Neil Powell said the staff changes were 'part and parcel of raising standards for the long-term'.

The board brought in an investigator earlier this year to look at the union's concerns.

But Colin Collis, from Norfolk NASUWT, said their concerns about the 'leadership and management' of the school, which has around 700 pupils, were ongoing.

He added: 'Parents will be rightly concerned if their children are facing an education in large classes as a result of staff illnesses or other factors.'

Three staff are understood to have been suspended and the changes mean three departments now have acting heads.

But the school said new teachers would arrive after Easter to bring staff numbers back to their 'full contingent'.

Mr Powell, who joined the school in summer 2016, told parents in his weekly newsletter he had to increase class sizes after the supply teachers they brought it were not 'of the standard we would have required'.

On March 17 he wrote: 'We have taken some immediate steps to deal with this situation over the final two weeks of term, including increasing class size to ensure that quality teachers teach all children.'

Mr Powell, previously head at Unity City Academy in Middlesbrough and East Point Academy in Lowestoft, said there had been 'some short-term pain in order to achieve a long-term gain'.

'Like many schools going through a period of improvement, one necessary step has been to review our teaching staff,' he said.

'Inevitably this has led to a period of transition, including the use of supply teacher cover while we recruit the permanent staff members who will take the school forward.

'We appreciate that this is not ideal, but unfortunately it has been a necessary step towards putting in place teaching staff for the long-term.'

But one teacher at the school claimed: 'Parents are coming up to me and saying 'what is going on?'. Staff morale is non-existent.'

The school was last inspected in 2015 by Ofsted and rated 'good'.