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By Erin Calabrese

Baltimore City Public Schools (BCPS) systems fired a teacher for calling her students, "Punk a** n******," Thursday, officials said.

BCPS CEO, Dr. Sonja Santtelises announced the firing after cellphone video surfaced capturing the teacher telling the children, "You are getting zeroes for doing nothing..." and later yelling, "Punk a** n****** going to get shot," when she attempted to remove a student from her classroom.

"The behavior in that video was not about a teacher trying to regain control of the class," Dr. Santtelises said. "The focus of our reaction was really about the way that teacher went about it and frankly the way young people were treated and addressed."

The mother of the student who was removed from the eighth-grade classroom, Erica Deminds, spoke at the press conference about how the teacher's outburst affected her child.

"It bothers kids to think that an adult thinks of them in a certain way, so for a teacher to think that you are just a punk whatever, whatever, you just want to get shot — this is what you tell the kids? It's not OK," she said.

Christopher Emdin, author of "For White Folks Who Teach in the Hood... and the Rest of Y'all Too," believes the first sign of trouble presented itself when the teacher is unable to engage her students in a positive way that recognizes and appreciates their culture.

"The one thing I know from teaching in urban schools, or any school for that matter is that when you have to threaten the students with a zero, you've already lost the class," he said. "They're not engaged. They're not ready to learn."

Emdin went further to say that the students in the video are clearly sending a "challenge" signal to the teacher expecting a reaction.

"...When you have to threaten the students with a zero, you've already lost the class. They're not engaged. They're not ready to learn." — Christopher Emdin

"If you're not teaching me then I'm going to push you to give me some fervor to get to work," he said. "They want you to give them some life. They want you to give them some soul."

Emdin said this is an important part of educating children from different socioeconomic and cultural backgrounds - when they challenge a teacher, that teacher must respond with some unique way to connect with the class. Think beyond handing out a simple worksheet, Emdin advises.

Chris Emdin conducts a summer workshop for teachers at Columbia Teachers' College where he is a professor, New York City, Aug. 12, 2015.Melissa Bunni Elian / NBC News

"An unprepared teacher will get angry," he said. "Anger is never an effective strategy."

There is a lesson to be learned for all in this instance but especially for administrators, Emdin asserts. The lesson is about cultural exploration and using the new knowledge gleaned from that exploration to engage with learning in a new way, one that starts with self-love and ends in real educational gains. Ultimately, through acknowledging who they are and their culture the students and teachers can remove barriers to real learning, Emdin said.

"They really need to think about who is going into that classroom to teach," he said. "If education is their profession, if that's what they love, then they have to do a lot of unpacking of their personal biases and strategies."

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This teacher more than likely came into this classroom with her own biases and in so doing, set off a reaction within her students that was undesirable, Emdin said.

"She didn't have the skill set to deal with this effectively," he said.

For Deminds, regardless of the biases the teacher may have, the whole situation caught her off guard. "She's a good teacher. I know her, I've talked to her before," she said. "It took me by surprise to see her in action like that because I've never witnessed it before."

Santtelises sent a strong message to everyone in the school district as she closed the press conference.

"Right now, here in city schools, we are clear we do not tolerate that type of language or interaction using hate speech with anyone let along our young people," she said.

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