An 8-year-old girl has been made to write an apology after trying to summon up the ghost of "Bloody Mary".
Her mother, who posted about the incident on social media, said her daughter went into the girls' toilet and stood in front of the mirror calling the name "Bloody Mary" five times.
Her teacher at a state primary school made her stay inside during lunchtime filling in a form about how she had infringed a school value of "taking responsibility" and writing that she would not do it again.
"It's pretty weird to make a kid miss a lunchtime for trying to summon a ghost," the mother said.
Friends who saw the post on social media responded incredulously with comments such as "Priceless".
The mother, who declined to be identified to protect her daughter, said her girl was just copying other children.
"It's been going round the school since the start of the year, she's kind of caught on to it a bit late," she said.
"She was just annoyed because her teacher thought she was swearing and she was thinking, why doesn't my teacher understand what it is?"
The mother said she had had "a lot of issues with the school" because she did not feel it was dealing appropriately with bullying, so she plans to move her children to another school.
NZ Skeptics chairman Mark Honeychurch said the teacher's response seemed "an over-reaction".
"There's going to be no ghost of Bloody Mary or anything that is going to come out of a mirror, it's a little bit of harmless fun," he said.
"I imagine the teacher has some kind of religious belief that would make her feel this is a bad thing, but teachers shouldn't judge people based on their own values."
However NZ Principals Federation president Whetu Cormick said the form that the girl was made to fill in was "a common type of reflective document that most schools would have".
"Children do all sorts of things and teachers make decisions and the mother actually would have agreed to the policies that were in place when she enrolled the child at the school," he said.
"Mums and dads should follow school policies and talk to the school and the teacher, and if they are not satisfied they should go to the board of trustees. It's unfair for people to be going straight to the media without talking to the school first."