How to address the use of the n-word by black students

Hi all.

I'm a teacher in a non-American country where the use of the n-word has started to gain popularity. This is especially noticeable amongst my black students and as a white teacher I'm unsure how to address it with them, or if I even should. I feel that it's not appropriate for school settings, but I'm also aware that I am missing distinct nuance with it as I am neither black nor American. As such, I would like to know how black American teachers address the use of the n-word by their students so that I can handle instances where it is used sensitively and appropriately.