Catholic school teachers in the ACT and NSW will walk off the job for one hour this morning, demanding fair pay for support staff and teachers.
Teachers at several schools will stand down from 8.30am to 9.30am on Tuesday, with additional industrial action at some schools in days to come.
The strike comes in the midst of a national teacher shortage, with Catholic school staff arguing they are stretched beyond capacity.
The Independent Education Union has previously called for a 10 to 15 per cent pay rise over two years and measures to cut paperwork, allow more planning time and end staff shortages.
Negotiations for Catholic school teachers new enterprise agreement began in early February.
Independent Education Union of Australia NSW/ACT branch acting secretary Carol Matthews said it was now November and employers were no closer to resolving pay issues.
Ms Matthews said teachers' salaries had been falling relative to other professions for more than a decade and this year's intensifying cost-of-living pressures had made matters worse.
"Salaries for support staff in Catholic schools are below those in government schools, yet Catholic employers are still dragging the chain on pay parity," she said.
"Our members are tired and frustrated with their employers' failure to respect them by negotiating in a fair and timely manner - they won't even discuss simple, sector-wide measures we know could mitigate workload pressure."
The union said practical action was required to reduce the administrative burden on teachers and allow sufficient time for proper lesson planning.
Ms Matthews said staff shortages were already severe and a fourth wave of COVID meant a response from employers was more urgent than ever.
"They are left with no option but to take action in an attempt to bring their employers to the negotiating table," she said.
The NSW Industrial Relations Commission handed down a decision to grant teachers in NSW government schools a pay rise of just 2.29 per cent in 2022 and 2.53 per cent in 2023, on Friday.
Catholic employers are not legally bound by the state government's decision.
However, the NSW government's wages policy was expected to guide their pay decision for Catholic school teachers.
Ms Matthews said these increases were not enough for independent school members or members of the NSW Teachers Federation.

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