JOPLIN, Mo. (AP) -- An elementary school teacher says she was just being funny when she taped a bag containing cat feces to the desk of a misbehaving student.

But the boy's mother isn't laughing. She wants the teacher suspended and her children transferred to a new school.

She says the boy has received several threatening letters, including one that appeared to be smeared with feces.

"The whole thing has gotten way out of hand," said Stephanie England, mother of 11-year-old Preston.

The flap began last week when Preston told his Jefferson Elementary school classmates to "suck a turd," his mother said.

The next day, teacher Diane Parker taped a bag of cat feces to Preston's desk and made him sit next to it for more than an hour.

Superintendent Vernon Hudson said the school was taking steps to deal with the situation, but he would not elaborate.

"It would have been fine if she had just sent home a letter saying my son was mouthing off in class, but instead she went ahead with this ridiculous punishment," Ms. England said. "This whole thing stinks."