One of the teacher strategies I'm most uncomfortable with -- both back when I was a kid, and now as a parent -- is the "blanket condemnation," wherein a whole class gets yelled at and punished for the transgressions of a subset of students. Even if most of the class acted up, it's hard on the kids who didn't to get lumped in with the trouble. It presses all of a child's "unfair!" buttons, and I've got to believe that mutes the teacher's message, as much as I can sympathize with how hard it must be not to lose your temper when faced with a mob of unruly children. My daughter is usually one of those who was not causing trouble, and yet she's also the one who takes the threats most to heart. Many times over the past couple of years she's come home all upset because a teacher threatened the whole class with failure, or detention, or repeating a grade, because some kids couldn't pay attention and do their work. It's a hard situation, because you also don't want the teacher saying, "You're all in big trouble -- except you, my one wonderful student, you never cause me any problems, dear." Better to be yelled at by the teacher than branded teacher's pet.
A similar situation happened when I was in the library the other day, with a fourth-grade class getting taken to task by the librarian for not listening to a guest speaker, and then again for being noisy while getting their books, and then again by their teacher when she heard what had happened. I was full of sympathy for those kids who got in trouble by association, because while many, many of the kids were loud and disrespectful, some were paying attention and checking out their books and keeping their heads down. I don't know how I would have reacted if my daughter had come home with this particular story of injustice ... but I'm not sure it would have been the same as the parents I heard about today. Apparently the teacher gave the class a homework assignment to write a note of apology to the librarian for their behavior, and a number of parents called the principal to complain because their little darlings had assured them they had nothing to do with it. Never mind that the librarian countered that they were in fact involved -- even if they weren't, are parents sending the right message in allowing their kiddos to blow off an assignment, however unjust? If it were truly punitive, maybe; but an apology note? How hard is that? "I'm sorry my class was so rude in the library. We will try to do better." It's not like they had to write "I will not talk in the library" 500 times. I think I would have told my daughter that it stinks, but out of respect for her teacher she should write the note.
Maybe I'm in the minority here. I remember a couple of years ago, the gym teacher was having a real problem with my daughter's class, and she told them they would all have to stay after school on a particular day. It never happened, though: So many parents complained and refused to allow their kids to stay that she had to cancel it. I'm all for advocacy, and I'm sure I've stood up for my kids in ways teachers thought were counterproductive. But if parents wonder why teachers can't keep control of their classes, they may want to look at the kind of messages they're sending. If mom's going to get you out of trouble, what's to discourage you from getting into it?