Pupils and staff at the school are angry after stadium opponents wrote "340 mill Chin Bin" over the school's recently-completed mural on the stadium fence.
The school was also tagged.
Its wooden Ravensbourne sign had the letters STS spray-painted on it and the school's forecourt was tagged with a message: "Don't use the kids".
Principal Megan Odgers was devastated by the damage - particularly to the mural in Anzac Ave - because it had cost the school about $1000 for the paint and to hire a relieving art teacher to design and help the pupils paint it.
"We certainly didn't do it to promote the stadium," Mrs Odgers said.
"We did it for art's sake, to promote the school and beautify Dunedin.
"It's a pointless exercise. It's destroying art work.
"They've hurt a community - they've hurt the kids. What is this teaching the youth of today?"
Mrs Odgers said if anyone was using the children to broadcast their own political views, it was whoever damaged the mural.
"Spray-painting the school - that is using the kids.
"They all walk past this way to come to school every morning."
She believed the graffiti was done on Monday night.
Dunedin Mayor Peter Chin said he was "horrified" there were people in the city "so mean-spirited".
"It's despicable.
"Here are genuine efforts by the community to decorate this fence, and it's come at a huge cost to the school.
"Not only is it a huge waste of money, it's hugely deflating to the schoolchildren who have put their heart and soul into it," Mr Chin said.
Stop the Stadium Trust president Dave Witherow did not condone the graffiti.
"We are completely opposed to graffiti and we're not in favour of targeting the white fence."
Mr Witherow said Stop the Stadium had 1500 members and the trust did not have control over them.
The damage may have been done by people making independent protests, he said.
"It shows how [annoyed] the community is with the council.
But we certainly don't condone it," he said.
Senior Sergeant Brian Benn, of Dunedin, said the incident was being investigated and asked anyone with information about the graffiti to contact the Dunedin Central Police Station.
Dunedin City Council Task Force Green staff managed to repair much of the damage to the mural and cleaned up the graffiti at Ravensbourne School.