That being said, if this kid had come to me before class and said he was expecting a possible call from his deployed father. I would let him answer and then take the call quietly out into the hallway.
The story is lacking in details but I'm going to give the school the benefit of the doubt here. The kid probably didn't discuss the possible call before class. The teacher would have no idea why the kid is answering the phone in class and past experience would be that the call is another in a long series of cell phone related disruptions. The teacher, needing to maintain classroom control probably ordered the student to cease their disruptive behavior and relinquish the offending device. The student being a child probably did not reason with the teacher effectively and mearly informed the teacher that they were talking to a parent. The teacher hearing that every time they talk to a child about illegal phone use probably did not assume that the parent was a serviceman and this may have been the last time the (from his own admission) troubled boy may ever hear from his father. Emotions most definitely got out of control. Probably by both the student and teacher. They're probably even more out of control as the kid doesn't sound like an honors student and the teacher probably has had disruptions from the boy before.
You and I know nothing of the past history of discipline issues the school faces with this student and classes in general. You and I don't know anything about the level of student commitment this class has. Today it's the cellphone from this kid. Tomorrow it will be the cellphone from another kid. Next week it will be an iPod.
That this made national news is an indication of how fucked up our priorities as a nation are. Snowflake there isn't going to learn that had he merely cleared the call with the adult in charge of the classroom prior to taking the call that things would have worked out. Instead the lesson is that kids can do whatever they want in the classroom so long as mommy goes to the newspapers to complain. What should have been a lesson in civility is now a public embarrassment for the school. Now every phone call is going to be from someones father in a war zone. Every disruption during instruction time is going to affect every student. The outrage here shouldn't from this one jackass kid and his parents. It should be from the parents of every other kid in the class over the loss of instruction time when these snowflakes lose control.
If the student had answered the call and said to me "This is my dad in Iraq. It's the only time he can call. Can I take this into the hall?" I would say yes even if he hadn't asked for permission before class. I doubt very much that is how the event played out.
(A side note here... If you are accused of disrupting classroom time and go on national TV to defend yourself, clean up. Every judge knows that criminals can borrow a suit but showing up to court in a dirty t-shirt shows either contempt for the seriousness of the charges or a lack of understanding about your end of the social contract. In either case, it's an indication to the judge that you may not belong in polite society. The same case is true here. I'm going to assume trailer trash dumbass and say the kid knows nothing about good manners.)