I tell you one thing.
Any teacher lays a finger on my kid in this manner, they better ****ing call the National Guard cause I'm goin Seal Team 6 on their asses.
Anyway, public school teachers are employed by the government so the question still stands - would it be morally or legally legitimate for public schools to introduce punishment beatings for misbehaved staff in exactly the same way they do for misbehaved students? If it's such an effective and important measure, why shouldn't it be extended to adults too?
"To waste, to destroy, our natural resources, to skin and exhaust the land instead of using it so as to increase its usefulness, will result in undermining in the days of our children the very prosperity which we ought by rights to hand down to them."~ Theodore Roosevelt (Message to Congress, Dec. 3, 1907)
It may be that your sole purpose in life is simply to serve as a warning to others.