Teachers at Prince Henry’s Grammar School in Otley, Leeds, struck for three days last week.
They were protesting at plans to turn the school into an academy called Otley Prince Henry’s Academy.
NUT and NASUWT union members have struck several times against the plans. This latest strike was an escalation.
Parents and school students have joined the picket lines.
There is huge opposition to the academy plan locally. At a vibrant 270-strong public meeting on Tuesday evening votes of no confidence were passed against the school’s chair of governors and head teacher.
Over 400 people marched through Otley on Saturday to protest about their local high school and swimming pool being handed over to an unelected body of five people who will form the new academy.
The fight will continue for local democracy and against the privatisation of education in Otley.