Teachers at John Port school in Etwall, Derbyshire, began a three-day strike on Tuesday of this week.
The workers, members of the NASUWT union, plan further strikes on Monday and Tuesday of next week.
Teachers are fighting plans to transform the school into a privately-run academy.
The three-day strike is an escalation in the battle as teachers held two one-day strikes last month.
Dave Wilkinson is branch secretary of Derby NASUWT and a member of the union’s national executive committee.
He said the strikes are becoming more effective. “The school is opening for fewer pupils than on the last strike day,” he said.
“Teachers at John Port school are bitterly opposed to academy conversion.
“It is time for the governors to end this madness in the interests of pupils and staff.
“They can end the strikes by accepting an NASUWT offer to postpone the earliest date of academy conversion to 1 September, opening another period of consultation and agreeing not to deduct salary for action short of strike action, which is designed not to affect pupils’ education.”
Workers have won support from parents and students—and some students are discussing holding their own walkouts.
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