Nice story and good job of parenting

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I've never really understood how people can be as ignorant as the teacher you mentioned in this post but your post clarified it for me a bit; Its taught too them as youth by their elders. Glad you were maybe able to turn the teachers child for the better. Hopefully he doesn't grow up to be as much of a fool as his parents.
I learned a similar lesson from my father when I was about 8-9 years old. He coached my little league soccer team. We lived in a predominantly white city. On the team we had a little boy who was the child of Indian immigrants. One day my father overheard one of the other boys calling him a Paki. The child was immediately told that was unacceptable and that he was to apologize and he wouldn't be playing in the next game. Needless to say the boys father was none too happy about this and proceeded to berate my father and then he threw a punch. My father cold clocked him and open up the taps on the guys nose

. The father and child never returned. Then I got the requisite violence doesn't solve anything but sometimes you have to stick up for yourself. Years later in junior high that same kid tried to get payback by sucker punching me but unfortunately for him the end result was the same; I opened up his nose.
Fast forward to today and the end result of those lesson my father taught me as a child is that I have friends of pretty much every race and religion and my life has been much richer because of it.