You see those comments on this sort of thread all the time. ‘Those kids just need a good spanking!’. etc.
Lack of consistency is one of the biggest things I see that hurts a person's attempts at avoiding chaos.
Also, kids will often behave and repeat whatever behavior receives attention. That attention may be positive or negative.
An example: A kindergarten I am familiar with, had a long standing practice of having a “baby” chair where children who misbehaved had to sit because they were not acting like “grown up” kindergartners.
A new teacher arrived. She simply could not “shame” children for their behavior, so she put to use the principle of noticing the behaviors she wanted, and rewarding progress.
Sometimes, however you need to get a child to stop what they are doing and it can not be ignored. For example, maybe they are talking and being rowdy instead of doing their work.
The teacher would look at the child sitting next the rowdy, and complement that child on being quiet and their wonderful work. When the rowdy became quiet and started working he got a complement too, as did the whole room which was also working diligently.
Problem solved and all the kids were in a good mood and with a positive attitude toward work. At the end of the year, the children receiving praise for their good behaviors had far better behavior than the ones who were punished and shamed for being babies.
Also there is a difference between punishment and discipline. Punishment is just that - it's done and over with.
Discipline involves discussion and a consequence and a way to demonstrate better behavior with respect to whatever the issue may be. A way to earn back a privilege for example.JMHO