Teachers at Eton College are considering whether to refuse to take classes in protest at proposed changes to their pensions, The TES has learned.
As thousands of state and independent school teachers prepare to go on strike next Thursday, union members at Eton, the public school attended by prime minister David Cameron and princes William and Harry, are also considering taking action.
While many of the 95 members of the ATL union at the world-famous Windsor school, which charges fees of up to pound;30,000 a year, are said to be reluctant to take part in a full strike, they are planning to meet on Sunday evening to decide what stand to take.
One option that will be discussed involves teachers refusing to take lessons and only providing pastoral care during the national day of action, in order to express their anger at the Government's proposals.
These include increasing teachers' contributions by 50 per cent, switching from a final-salary to career-average scheme, and gradually raising the retirement age.
Around 22,000 ATL and NUT members in the independent sector were balloted on whether to take part in the industrial action.
More than 7,000 voted, with the strike backed by 83 per cent of ATL members and 89 per cent of teachers in the NUT, but heads are still unsure how many will actually go on strike.
Berkhamsted School in Hertfordshire, another leading independent school, faces severe disruption and will be partially closed for the day.
Headmaster Mark Steed told The TES that he expected "60 to 70 per cent" of his teachers to go on strike.
He said 96 out of the school's 107 ATL members had voted for the strike, and that he expected a "large majority" would take to the picket line on Thursday.
Three trips planned for Thursday by the school, which counts author Graham Greene and Sir Winston Churchill's wife Clementine among its alumni, are expected to go ahead, but Mr Steed said the school would effectively operate on a "snow day" footing.
"I suspect we will be able to put something on, but it won't be normal teaching. The teachers want to show professional solidarity with those in the maintained sector, and show they are all in it together.
"There are very strong feelings about this, but the problem is that it's not inconveniencing the Government one iota by them going on strike," he added.
At prestigious Winchester College in Hampshire, around 70 per cent of teachers are union members. A spokesman said school leaders were still waiting for union leaders to inform them how many teachers were planning to strike.
Geoff Lucas, secretary of the Headmasters' and Headmistresses' Conference, which represents the heads of 250 leading independent schools, said most of its members were still waiting to be notified of how many staff were planning to strike next week, but he did not expect any to be forced to close for the day.
He said some heads were very unhappy about their staff taking action when it was the schools, rather than the Government, that would suffer as a result.
"There are many heads who are sympathetic (to the strikes), and a lot who are unhappy with the disruption which will be caused by the industrial action," he said.
"What our members find difficult is that the target of the strikes is the Government, not the schools, and some heads are very unhappy about the prospect of action which is not targeted at the right people."
Eton's headmaster Tony Little was unavailable for comment.
Original headline: Not too posh to protest: Eton staff may join pension strike