Teachers from the public and private sector left their students to take a stand on the final day of the #KidsOffNauru campaign on Tuesday at Victoria's parliament house.
"It's so important because teachers understand what is going on on Nauru and Manus Island, we can see the human rights abuses that have occurred, that still are occurring in Australia's name," Teachers for Refugees spokeswoman Lucy Honan told EducationHQ ahead of the rally.
"A lot of teachers teach kids who have come off Nauru or who have come from different refugee backgrounds and been subject to Australia's detention regime, and we can see very clearly the impact of Australia's policies of deterrence on the lives of our children and their families and it's of grave concern to us."
"We're mandatory reporters, we are responsible for the wellbeing of our students, we are responsible for speaking up when something is wrong and we can see very clearly that it's wrong..."
Mehdi, an Iranian refugee on Nauru, was live-streamed to the rally along with other speakers including former Nauru teachers.
With people still on Nauru and Manus islands, and 16 children in a detention centre in Melbourne, the teachers want the Federal Government to resettle them in Australia.
Honan said that the issue is affecting classrooms around Australia.
"We can see first-hand the impact of the racism, definitely. I think you would be hard pressed to find a teacher who hasn't noticed an escalation in racism," she said.
"Anybody who taught a child from a refugee background knows that there is a lot of work, a lot of really important work that teachers do, investing in trying to mitigate some of the experiences that those children have had."
A spokeswoman from the Department of Education and Training said teachers are free to support causes in their own time but they should not use their professional position to make political statements.
"Teachers have a role in encouraging students to consider and think critically about a range of perspectives on complex issues being debated in the community," she added.
Teachers will also rally in Queensland as part of the campaign.