Clare Fletcher, new executive head teacher of North Walsham's Manor Road junior, and infant and nursery schools.

Parents whose children have just begun a new year at a north Norfolk school have been told that it has been placed under special measures.

Government Ofsted inspectors say North Walsham Junior School is “inadequate” in four out of five categories, including the quality of teaching, leadership and management, and pupils’ achievements.

But the school’s new head teacher, Clare Fletcher, says a raft of improvements have already been introduced.

Although Ofsted visited the school in late June, the inspectors’ findings were only made public this week.

Their visit had been a “bolt from the blue”, according to Mrs Fletcher, now executive head teacher of both the Manor Road junior and neighbouring infant school and nursery.

The two schools had formally federated on June 1, with a combined governors’ body and head, and Mrs Fletcher, who has been head of the infants’ school for 10 years, officially took up her new executive role on September 1.

But she unofficially stepped in to the breach when the Ofsted inspectors arrived because junior school head teacher Ruth Brumby, who was due to retire at the end of the summer term after 18 years in post, had taken authorised leave from mid-May.

The junior school had received an overall “satisfactory” ranking last summer and the inspectors’ findings had been “devastating,” said Mrs Fletcher. Their sole “satisfactory” grade had been for the children’s behaviour and safety.

“It was a real roller-coaster for the staff, who were coming to terms with saying goodbye to a well-regarded head.

“They didn’t understand the difficulties they were in because the school was running smoothly. They have been absolutely wonderful in coming behind me to turn things around.”

On the two days immediately following the inspectors’ visit, Mrs Fletcher said the staff of both schools had undergone intensive maths training.

The infants’ school was ranked “outstanding” by Ofsted in 2008 and 2011 and Mrs Fletcher said its successful ReadWrite and maths-teaching systems, practices and policies were now all in use at the junior school too.

“In a way it’s been a positive thing because the inspectors’ report gave me and the new governing body a mandate for change,” she added. “It feels like I’m inventing a school from scratch.”

Paul East, chairman of the combined governors’ body, said they were finally heading in the right direction. He added: “I am confident that rapid progress will be made.” The schools have a total of 570 pupils.