Dundee secondary school teachers will stage a one-day strike this month over council plans to replace department heads with a new faculty system.
Members of the Educational Institute of Scotland (EIS) union voted by 88% to 12% to strike on 22 June over the move.
Dundee City Council said faculty models were in place in most local authority areas and benefited young people.
The EIS said the plan would "remove the vital experience offered by subject specialist principal teachers".
The union said a council statement this week re-emphasising its plan was an "act of provocation".