Yes, you said:
My point is she clearly was doing something to get kicked out of class. In danger of being Turk, we don't have the whole video. I don't know what she was doing, but I'm willing to bet she was being obnoxious which lead to the incident to begin with.
Does that justify his behavior? No.
As far as it has been reported, she pulled out her cell phone in class for a moment and the teacher asked for it. When she refused to give it to him, he called for an administrator. Par for course for a teenager. It doesn't seem to rise to the level of obnoxious kid IMO.