Some support staff in Dundee schools have voted to strike for two days in September.
Members of the GMB union have rejected their latest pay offer.
They are now warning of potential disruption on September 13 and 14, unless a deal can be reached before then.
The impact on Dundee schools is unclear, with members of other unions yet to confirm their intentions.
But it could mean more chaos for pupils and parents, who have already faced disruption due to strikes involving teachers and support staff in recent months.
Two days of strike action planned at Dundee schools
GMB says it cannot confirm how many members in Dundee are involved, but says staff work in catering, cleaning, pupil support, administration and janitorial services.
Teachers are not part of the planned action.
It comes after a ballot saw 94% of members across the country reject a council pay offer – made through umbrella body Cosla – of 5.5%.
GMB claims the offer would mean the lowest-paid Scottish workers are getting less of a pay rise than their equivalents in England and Wales.
Keir Greenaway, GMB Scotland senior organiser for public services, says talks next Friday will be the last chance to avert the strikes.
He said: “The latest figures show that, despite rising wages, pay is still being outstripped by inflation.
Cosla says its made a “strong offer”
“The pay offer to council workers does not come close to matching the surging cost of living and one that is worth less with every month that passes.
“Scotland stands on the shoulders of our local authority workers and the value of their work must be reflected in their salaries.”
Colsa, the body which represents Scottish councils had refuted the union’s claims saying it’s made a “strong offer” that seeks to protect jobs and services.
A spokesperson added: “While the offer is 5.5%, the average uplift on salaries going into the next financial year is 7%.
“Those on the Scottish Local Government Living Wage would get 9.12%.
“In addition, those at higher grades, where Councils are experiencing severe recruitment challenges, would see 6.05%.
“It is an offer which recognises both the vital role of the people who deliver our essential services across Councils every day.
“Crucially, it also raises the Scottish Local Government Living Wage by 99p to £11.84 per hour and sets out a commitment to work with our trade unions to develop a road map to £15 per hour in a way that protects our workforce and services we deliver.”
Commenting on the threat of strike action a spokesperson for Dundee City Council said; “We’re monitoring the situation and will inform families about any developments.”
