A teacher has described how she locked her class in to protect a pupil when he was threatened by another child. He was beaten up anyway because the aggressor waited outside for him until the lesson ended, she said.

The shocking scene was described by one of the teachers who walked out in protest over what they say is failure by school management to address serious behaviour problems at Pencoedtre High School in Barry. The Nasuwt teaching union says staff and children at the 900-pupil school are at risk of harm because the situation has got so out of hand.

The union said that since September 2023 there have been more than 50 serious incidents of abuse at the school, which was put in Estyn special measures last year and is looking for a replacement headteacher and you can read more about that here.

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Describing how she locked her class in for safety the teacher said it was not an unusual episode. She claimed that both girls and boys were involved in physical and verbal violence "every day" and "every hour" at Pencoedtre.

"We had a child threaten another pupil and were told to lock pupils with us in the classroom to keep them safe. I taught the class and at the end the aggressor came back.," she said.

"I had locked in the entire class but at the end of the lesson I had to open the door to let pupils out and the aggressor was waiting. The aggressor assaulted the victim in front of staff.

"The victim was very severely assaulted and they had to go home and get medical attention. Several staff were pushed into walls and had their arms bashed trying to intervene."

The front entrance to Pencoedtre High School in Barry
Pencoedtre High School in Barry

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The teacher, who we are not identifying to protect her, said she, and other staff, were deeply upset they had not protected the pupil when he asked for help. She said they felt they had let the victim down.

"The victim was traumatised having sought help from adults who did not protect them. This type of thing has happened on more than one occasion."

She said staff at Pencoedtre have had their glasses broken into their faces trying to step in and break up fights. They also risk legal action from children if they intervene.

"The main thing is safety and we cannot keep children safe in our care. We have staff intimidated by children who find it hard to come back in when they are not punished. It is these sorts of things that have led to the strike. Strike is a last resort.

"Some children are absent because they are frightened to come to school. There is also staff absence and supply teachers do not want to work here - people simply don't want to do the job."

The school's former head Lee Humphreys left last year and Pencoedtre is currently run by an acting executive head Debra Thomas and acting head Leanne Pownell. The teacher and the Nasuwt stressed they are in dispute not with them but with the local education authority for failing to take more urgent steps to address matters.

The Nasuwt said a major problem is having a mini pupil referral unit and autism base housed in the centre of the school building. While it's not unusual to have these bases on site, the location is unusual, said Nasuwt representative Sharron Daly.

"It is not good enough for the council to say they will resolve all this in 12 months. In that time people are suffering and their education is being damaged," the teacher said.

"If I was a parent of a child at this school or in the units or PRU I would be appalled at the way they are being failed."

Pencoedtre was shut to all but exam pupils on January 10 when 46 members of the NASUWT Cymru went on strike in protest. Another union, the NEU Cymru, also has a mandate to strike on the same issues, but has no dates for walk outs yet.

In a joint statement from the Vale of Glamorgan Council and Pencoedtre High School said they are disappointed by the strike action. The statement added: “We are fully aware of the issues affecting staff and are working with the NASUWT to resolve them.

“The work taking place has been discussed with the trade union in regular meetings and includes steps to improve the working environment and update the school’s behaviour policy. All staff will undergo specialist, ongoing training, with a significant number involved in training this week.

"This professional development is designed to improve teaching and learning. It will also help create positive relationships with all pupils and is focused on addressing Estyn recommendations following the recent inspection. The local authority, senior leaders and governors are committed to actioning the post-inspection action plan (PIAP) - this includes improving the provision to address the behaviour of a minority of pupils who have trauma-related issues.

“Staff and pupil safety is of the highest importance and any incidents that impact this are taken extremely seriously. They are subject to robust investigation and accurate recording, with subsequent action taken in line with appropriate policies.

“These include the school's Disciplinary Policy, Welsh Government Statutory Guidance for Exclusions and the Additional Learning Needs and Education Tribunal (Wales) Act."

“There are lockdown procedures in place at the school to deal with significant incidents and these are used proportionately.”

Pencoedtre High, which opened in 2018, was formerly Bryn Hafren Comprehensive School when it was girls only. Pupils and staff moved into new-build £22.8m premises in January 2022. Nasuwt Cymru is now in dispute with nine schools across Wales, five of which are centred on behaviour.

A further five days of Nasuwt walk outs are planned for January 18, 24, 25, 31 and February 1 unless the situation is resolved before.

Nasuwt general secretary Dr Patrick Roach said: “Vale of Glamorgan Council is failing in the most basic of statutory remits: to keep employees and children safe. The situation at Pencoedtre is a serious concern.

"Nobody should fear physical or verbal abuse at work or be expected to put up with it as part of the job.

“We should never ask teachers to work in classrooms where pupils are afraid of other pupils. No student can learn or progress in that environment. The council must move immediately to protect everyone at Pencoedtre.”

Neil Butler, Nasuwt national official for Wales, said: "Strikes are a last resort for Pencoedtre’s dedicated teachers. There are some pupils at the school whose complex needs can only be met at a specialist provision, but no places have been offered - this negligence is causing immense distress for everyone.

“School management is eager to resolve these issues and the executive headteacher has put forward a number of practical solutions but Vale of Glamorgan Council refuse to implement them within a safe and reasonable time frame. Their actions are likely to cause harm to the teachers, pupils and school staff under their duty of care.

“Pencoedtre is just one of a number of schools in Wales where the NASUWT is in dispute over learner behaviour. This is a national crisis that the Welsh Government needs to get serious about.”