In a case of the devil you know, an Indiana high school is trying to teach students what not to say by having them write it down.

In a lesson on cursing, students at the Thomas Carr Howe High School in Indianapolis were asked to spell out the curse words they know.

"And everyone was nervous about it and uncomfortable about it, to write it in front of an adult, especially a teacher," Grade 7 student Viazell Gaither told CNN.

The kids were then asked to say the words aloud and explain to their classmates they are offensive.

School officials say the unusual lesson is a means of allowing teachers to gain some measure of control over what comes out of their students' mouths, and has had some effect when used in the past.

Students were given the option of excusing themselves if they were too uncomfortable with the exercise.

Formerly a part of the Indianapolis Public Schools system, T.C. Howe High school was taken over by the state-appointed turnaround company Charter Schools USA in July.

Students at T.C. Howe wear uniforms, but do not pay tuition.

According to the school's website, the school adheres to the same code of conduct governing all public schools in the state, "and may incorporate additional codes as necessary for students to continue to achieve academically."

That includes "Character Education programs."

The state is struggling to turnaround a dropout rate that saw nearly 40,000 students quit school early between 2005 and 2011.

While the use of curse-filled language remains linked to perceptions of one’s manners and behaviour, what was once too profane for polite company has changed in recent years, as once socially-forbidden words have crept into the mainstream.

The tension remains, however, between those who believe highlighting such language discourages its use, and those convinced it’s more of a vocabulary-building exercise.

A school in the U.K. re-ignited that debate in mid-July, when it was reported 11-year-old students there had been asked to grade uncensored curse words on a worksheet titled "Acceptable or Not?"

The list of phrases – including the notorious F- and S-words alongside others such as “bugger off” -- asked students to mark whether they were always, conditionally, sometimes or never okay for conversation.

In response to the outcry spurred by reports of its curse-word curriculum, the Shafton Advanced Learning Centre in South Yorkshire said it was undertaking the lesson, "As part of our social responsibility."