More than 3000 public school teachers have rallied in Adelaide, vowing to take up the fight for better wages and conditions to the South Australian government.
But Treasurer Rob Lucas criticised the action declaring no amount of "flag-waving or singing John Farnham songs" would improve student outcomes or change education funding in the budget.
Thursday's rally came amid a half-day strike by teachers across SA, the first walkout for 10 years after negotiations stalled on a new enterprise agreement.
It closed off Flinders Street in the city as teachers converged on the education department headquarters.
Australian Education Union state president Howard Spreadbury told the rally the government had underestimated the resolve of teachers on important measures including smaller class sizes, sustainable workloads and better pay.
Teachers also want more resources for special needs children and more support for country schools.
"We are proud, we are passionate and we are committed to the students of this state and to public education," he said.
"We will take this fight up to the government for as long as it takes."
As well as the big city turnout, rallies were also held in regional centres across SA.
Ahead of the strike, Mr Lucas described the action as "puerile in the extreme" but said on Thursday the government was prepared to sit down with the union and work out how best to spend education funding.
"There needs to be a reasonable salary increase but there needs to be enough money there for literacy and numeracy programs," he said.
However, the treasurer urged the union needed to "back off" on some claims, including demands for more non-contact time which he said would cost $59 million a year.
"Those sorts of claims, we just can't afford," Mr Lucas said.
The government said less than 200 of SA's 875 schools and pre-schools closed as a result of the action with a further 194 operating on modified programs.
© AAP 2018