There are lots of things wrong with the public schooling system nowadays. If there’s a finger you can point the blame to, then it’s the student population that’s usually wrong, though the faculty is not excluded. Regardless, the amount of degenerate students that are disruptive, and insubordinate are especially high when they come from the urban areas. They ruin the learning experience for their peers, and some schools majority student population are actually these type of people.
If it the student is causing physical harm or about to cause such harm, then it is within the right of faculty to use physical force to restrain the students. While parents can cry that no one should touch their child, perhaps they should be raising their child to be better behaved first.