I taught for 25 years in small town New Hampshire. In almost every case when there was a disrespectful problem student, there was a similar problem with the parent.
I have no solution for the teachers, but great respect for the job they are doing. Putting the blame on the school or the teachers does not help the situation, simply results in low morale.
Last week there was an article about charter schools. Did it not occur to anyone that the reason they have good results is not because the public schools are doing a poor job, but because charter schools are selective? Private schools and charter schools can pick whom they admit, and parents who enroll their child expect good results from that child. The public schools do not have that option.
I hope the community will get behind the schools and help them come up with viable ways to improve the situation. If not, it will have to cope with these students when they are adults, as many will come to bad ends. I have seen it happen.