HICKORY, N.C. -- The families of some Southwest Elementary School students are angry because they say a substitute teacher acted inappropriately last week.

A letter went home to parents on Tuesday afternoon that does not describe the actual incident in Hickory, but does explain that the woman’s actions were not acceptable.

The families of four children said the substitute tied the third-graders up with a jump rope on the playground.

Delores Ivanko said she could tell something was wrong with her grandson after school.

She said she later learned the students were bound because they were too loud in the classroom.

"The teacher told them that this is what's going to happen to them when they go to jail," Ivanko said.

She said the four boys were told to stand with their backs to each other and then the rope was tied around them.

"Dragged them with the rope, with the boys crying down a ramp out onto the playground for a half an hour, and left them there," she said.

The Hickory City School District said the substitute managed the students in an inappropriate manner and no longer works in the schools there.

A mother who asked not to be identified said the principal called to apologize.

"He actually had a mark on his side where he had been pulled, from where the rope was, and there's no excuse for that," she said.

School district officials said they do extensive background checks on all substitute teachers. They said there were no red flags with this teacher, who's worked in the school system since 2004.

Jennifer Couch, whose daughter is in third grade, said she believes the discipline went too far.

"If it was my third-grader, I would absolutely hit the ceiling," she said.

School district officials said they have not contacted the other two school systems in Catawba County, but they have put something in the woman’s personnel file, which could be checked for future employment elsewhere.