to stop being punished for hairstyle

Children are being punished for having short hair which has nothing to do with how they learn . Teachers shouldn't expect parents to have to keep paying money every week to have hair cut has they have other bills to pay for to make sure there child has food , water and a roof over there head ... they should let the child have the style they want .
I don't understand why the teachers can have there hair and make up and wear the clothes they choose to but the child gets punished or excluded which then goes against there attendance