Schools across Scotland face weeks of closures and disruption after a third union rejected a new pay offer.
Unite has joined Unison and the GMB in turning down the proposal from council body Cosla. All three have warned time is running out to avert strike action.
Parent groups have raised fears school closures will have a “detrimental” effect on their children.
But on Thursday Cosla said there was no more money available for pay without cuts to jobs and services.
The latest offer from the body, which represents Scotland’s 32 councils, is a two-part plan which it said would give workers at least a £1,929 increase in annual salary by 1 January 2024.
The decision to reject this means three out of four schools could be closed by a programme of strikes beginning with a three-day walkout on 26, 27 and 28 September.
On Friday Unite general secretary Sharon Graham said: “It has taken Cosla five months to increase their offer by a measly 38 pence a week for the lowest paid council workers.
“Unite’s local government representatives rightly rejected this offer. The fight for better jobs, pay and conditions in local government goes on, and if needs be by strike action. Unite will back its members all the way.”
Unison has already said Cosla has until 20 September to “significantly improve” the offer and prevent walkouts.
GMB Scotland dismissed the latest offer as “far too little, far too late” to avoid the upcoming strikes.
‘Frustrated’ parents
Speaking on BBC Radio’s Good Morning Scotland Leanne McGuire, of the Glasgow City Parents Group, said the latest strikes felt like “history repeating itself”.
It is the fourth year of disruption following the Covid lockdowns and teacher strikes.
She told the programme: “My concern is that we start to feel that this is the new normal in schools and it really shouldn’t be.
“Pupils should be able to get through their full school year without any disruption, regardless of what that disruption is for.”
Ms McGuire said there was a lot of sympathy for the striking workers and anger at Cosla, the councils and the Scottish government that the dispute had not been settled.
She added: “When these talks come down to the wire, that’s where families get really frustrated because we don’t know what plans to put in place.
“That’s where people start getting really frustrated about it.”
Robert Woolley, of the Highland Parent Council Partnerships, said he was worried school closures were having a detrimental effect on pupils who were forced to learn alone at home.
“I think it’s detrimental to the social aspect of life being stuck behind a screen. It’s not normal. You worry about the future of your children,” he said.