Sister Kathy Avery said she wouldn’t tolerate any swearing on the playground and read out a list of words which she considered abusive.
The principal of St. Clare of Montefalco Catholic School had students stay after a Mass last month and informed the fifth- through eighth-graders that she has a zero-tolerance policy for cursing.
Just in case anyone was not sure what she was talking about, Avery read off a list of the very words and phrases that she was banning.
"It got a little quiet in church" during her talk, she told the Detroit Free Press.
Some parents were shocked, but others applauded, the newspaper said.
"In a way you would think a nun would shy away from something like that, but she's very open with the children, very clear in her messages," said Margaret Roache, chairperson of the school commission.
Roache's sixth-grade son was there when Avery read the list of banned words.
"When I asked him to give me a sample of it, he said 'Oh, no, I can't say it!"' Roache said. "I thought it was great."
A representative of the Archdiocese of Detroit declined to comment Sunday.
Curse words are not the only things that set Avery off. She has also banned the words "stupid" and "boring."