The protesters say there is no justification for closing Belmont
Teachers at a County Durham school have gone on strike in protest against moves to turn it into an academy.
Pupils at Belmont School were told to stay at home for the day. Only Year 11 students, due to take GCSE exams, were being taught.
The union NASWUT said it had not ruled out further strikes over the plans for a 1,200 place "super school" to replace Belmont and Durham Gilesgate College.
Durham County Council said the action was "disappointing".
Simon Kennedy from NASUWT said the action had not been taken lightly.
"The reasons fall fairly and squarely with county council, which made a decision that staff, pupils, parents and the community opposed," he said.
We believe everyone is behind us and we will win this dispute
"Belmont is among the top 5% of schools in the country, there's no reason for it to become an academy. It's an excellent school."
He said that staff at other affected schools - there are three academies planned by the council - were also considering their position, and that further strikes at Belmont had not been ruled out.
"We believe everyone is behind us and we will win this dispute," he added.
David Williams, Durham County Council's corporate director of children and young people's services, said: "It is inevitable that as part of any school reorganisation some staff may feel uncertain about what the changes might mean for them.
"We recognise that staff may have concerns and we have already arranged to meet trade union representatives to discuss these issues.
"It is disappointing that this industrial action, which could harm the education of young people, is going ahead before this meeting has taken place."