Leaders of a small secondary school say Ofsted inspectors have judged it to be failing because of its “lack of a fence”.

Kirkby Stephen Grammar School has revealed that it is being put into special measures just weeks before it welcomes the Princess Royal as part of its 450th anniversary celebrations.

Headteacher Ruth Houston and Simon Bennett, chairman of the governing body, have vowed to appeal against the inspectors’ judgement.

They say the school was praised in “almost all aspects of its education” but criticised for its “inadequate site security”.

The school’s safeguarding efforts are deemed to be “inadequate”, as is its overall effectiveness following a two-day inspection in January.

Leaders have been criticised for not putting appropriate measures in place to “minimise identified potential risks” to pupils.

Staff have also failed to keep adequate registers of sixth-form students, which inspectors say means they are not able to “take appropriate action to ensure students’ safety”.

Mrs Houston and Mr Bennett say steps to address security issues will be published on the school’s website within two weeks.

Concerned parents can also attend a drop-in session at the 375-pupil school next Thursday.

In a letter to parents, Mrs Houston and Mr Bennett said: “A school should be defined by what goes on inside its classrooms and not by its buildings or location.

“It is a failing of the inspection system, not the school, if an overall judgement is defined by a lack of a fence or not enough locks on doors rather than the excellent teaching, leadership, behaviour and outcomes of the school.”

Inspectors were unhappy about security arrangements the school had in place, a stance which Mr Bennett said “trumped everything else”.

He said: “Of course we take safeguarding of chil-dren extremely seriously.

“On every statutory measure the inspectors found no significant problems and our students told inspectors they feel safe and secure here.

“Governors and staff had already assessed the safety of the school site given its location and the rural community it serves and believe we have taken, and continue to take, all precautions necessary for our circumstances. Clearly Ofsted has a different agenda.”

He added: “Putting the school into special measures is not the appropriate way to deal with this issue.

“We are a good school with an outstanding fence issue.”

Mrs Houston said: “While we don’t believe students are at significant risk from intruders we will, of course, do what we can to address Ofsted’s concerns but our priority remains to deliver the best teaching we can so that our young people have the best start to their adult lives.

“I am confident that once additional security meas-ures are in place Ofsted will give us the overall judgement our school deserves.”

The school will now receive regular monitoring visits until inspectors are satisfied issues have been addressed.

In 2013 the school was judged as good.

Cumbrian safeguarding expert Kym Allan, of Kym Allan Safeguarding, Health & Safety Ltd, said: “Without evidence, it is difficult to see how four years later, the pupils are now at such a high risk of violence from intruders.”

Mr Bennett also believes that the implications of the judgement could have ramifications for many schools.

The judgement comes just four months after government inspectors raised concerns about site security at Ullswater Community College in Penrith.

Mr Bennett said: “We have already drawn up plans to tighten school access but a small school such as this has a very limited budget and having worked so hard to put the school on a sound financial footing over the last four years we have few resources and will not divert money from teaching.

“Judgement such as this could have catastrophic consequences for many schools in Cumbria.

“There simply isn’t the cash, or the need, to be turning rural schools into prisons.”

A statement from Ofsted said: “Inspectors look at a wide range of evidence when evaluating the effectiveness of safeguarding in schools, and they will not normally find safeguarding to be ineffective because of a single shortcoming, such as site security.

"Ofsted will assess how well school leaders and teachers understand safeguarding risks, and whether they know what to do if a child faces potential harm.”