Harlem Park Elementary/Middle School said in a statement on Thursday the science teacher was no longer employed after engaging in "verbally abusive behavior" and having "made racially charged comments directed at students."
The video, shot by a student on Tuesday, shows the unidentified teacher removing a student from the class before returning to class, where she says the N-word. The video shows the stunned reaction of one of the students, while others can be heard shouting "racist." At one point, she called the students "idiots."
The teacher is white; most of the students in the classroom are black.
"I was floored, I was utterly disgusted," Erica Gales Deminds, who has three children at the school, told CNN of her reaction when she first saw the video.
Her son had been put out of class by the science teacher before she used the word. The video clip only shows 50 seconds preceding the use of the N-word and cuts off shortly after its use.
"The students were being rowdy, they were being disruptive, they were being teenagers pretty much," Deminds said.
"The teacher was a really good teacher, she was one of my son's favorite teachers. I had met her a few times and she was always very pleasant," adding, "she just must have reached breaking point."
After her son showed her the video, Deminds shared the video on Facebook, where it was viewed more than 1 million times in just over 12 hours. The parent went to the school to complain and was told of the teacher's dismissal.