Ysgol Uwchradd Tywyn hit by NASUWT teachers' strike
Members of a teaching union are striking for three days at a Gwynedd secondary school over job cuts and changes to their contracts.
The action by NASUWT teachers at Ysgol Uwchradd Tywyn starts on Tuesday.
The union said members had no choice but to take a stand to protect their jobs after the local authority showed a "lack of willingness to negotiate".
Gwynedd council said the strike affected only one school and it would remain open during the strike.
Rex Phillips, the NASUWT Wales organiser, said: "Despite the efforts of the NASUWT and the offers made to avert strike action, neither the governing body nor the Gwynedd authority has, to date, brought anything to the table in order to resolve the dispute.
"We remain open to further negotiations and I hope the authorities will make meaningful contact so that this dispute can be resolved quickly as possible."
The union has held two day-long strikes at the school during the summer.