No she wasn’t. She disrupted the class room by arguing with the teacher. The teacher requires total silence in the classroom which includes responding to sneezes. Seem silly but I can see 30+ students deciding to shout out “Bless you” all at once and interrupting the class for several minutes. So from a teacher’s view point it is probably necessary to instill a total ban on talking. The point is that saying “God bless you” is not forbidden because it is “godly speaking”.
That is just stupid.
Did you miss the part the student said her teacher told her that was for church?
Did you also miss the word is on the teacher's banned word list?