So we must answer these question.
1. What to complain
and 2. How to file a complain?
To the point answer will be the correct way to complete the letter.
Here is a sample letter for a student who had been beaten by another miscreant student.
Question: Write a complaint letter to the class teacher against a student who has recently beaten your son or daughter severely.
The Class Teacher,
Respectfully g beg to say that one Student named xxx had been severely my son (XXX) on his back at the time of school closing period on 18-02-20/4 . g noticed a dark spot at the back of my son .
(xxx) had been misbehaving physically my son for whole session of class Iv . 9 ignored and thought that the problem might got solved .
But this time the matter has crossed the bearable limit .
I therefore request you to kindly take necessary disciplinary action against (xxx) and oblige.
Thanking you ,