Teachers at a Birmingham secondary school struck against plans to turn the school into an academy on Thursday of last week.
Around 40 strikers joined a picket line outside Hamstead Hall School.
The walkout closed the school to students in three year groups and restricted classes for others.
Design and technology teacher Peter Jones said, “The number of teachers out on strike clearly shows the strength of feeling.”
He added that the strike was “the only way of getting our voices heard”.