"I think it's appalling that a public school for children would pull this nonsense."
The school website says the school disco, on tonight between 7 and 9pm, for years 7 and 8, has a 1980s theme, and encourages children to come dressed in clothes from that decade.
A Facebook post promoting the event was deleted minutes after the Herald contacted the school.
Wairau Intermediate School Principal Grant Murray told Newstalk ZB that the school policy is to alternate between boys and girls bringing a plate each year.
"We alternate it [the pricing] each year," he said.
"So some years we ask the boys to bring two dollars and a plate.
"We started doing it because if we asked everyone to bring a plate then we'd end up with too much food."
The permission slip for the disco in 2017, sent to the Herald, showed boys were asked to bring a plate that year.
"Admission will be: Girls $5.00 and Boys $2.50 plus a plate of finger food which does not require heating," it said.