Tens of thousands of government school teachers, principals and education support staff are set to converge on Melbourne’s CBD as part of a long-running campaign to boost pay and conditions.

Victorian teachers and public school workers will walk off the job for the second time in four months on Thursday after rejecting the government’s latest pay and conditions offer.

Victorian members of the Australian Education Union voted to turn down the state government’s updated offer of a 28.3 per cent pay rise over the next four years.