The National Association of Head Teachers (NAHT) announced on Thursday it will ballot its members for the first time ever over whether to strike on the public sector pension row.
If members vote to strike it will be the first time in the union's history since its set up in 1897. Members will have from September 29 until noon on November 9 to vote, and then the union has a four-week window to set a date.
Some members from other teaching unions have expressed concerns any more strikes will not be effective unless the unions cooperate with one another.
Katie, a secondary school teacher and National Association Schoolmasters/Union of Women Teachers (NASUWT) member from Berkshire, said: "It's all very well striking, but when half the teachers strike it doesn't mean the school has to close. All that happens is the other half, who belong to the National Union of Teachers (NUT), have double the work as they have to cover lessons.
"If head teachers decide to strike, the only people it will probably affect are other teachers as they will have to step up and take on extra responsibilities to compensate."
A spokesperson from NASUWT said: "We don't tend to comment on other union ballots but we will bear in mind other union action when planning our timetable. Nothing else has been decided yet."
But Christine Blower, general secretary of NUT took a more proactive stance on working with other unions to coordinate strikes.
“The NUT warmly welcomes the decision by the NAHT to ballot its members", she said.
"We are working with six other teaching unions - including the NAHT - on a petition of teachers and a lobby of Parliament during half term on the 26 October. The NUT is also fully committed to the TUC day of action, 30 November."
Huffington Post has contacted NAHT but they have yet to comment.