NEU union members at Acton High School in Ealing, west London, struck on Tuesday. The walkout follows a 24-hour strike last Thursday and a two-day strike last month.
Strikers are fighting bullying, management’s response to behaviour issues and a planned takeover by Ark.
Ealing NEU divisional secretary Stefan Simms told Socialist Worker the strike was solid.
“We know that 109 were on strike out of 117,” he said.
“We’ve done lots of leafleting and a majority of responses from parents and others support us.”
Workers plan a two-day strike from next Tuesday and another two-day strike the following week.
Then they plan three-day strikes until the end of term.