Mine was a similar situation - a rural public school system in the deep southern U.S. The ratio at that time was about 55% white, 40% black, 5% Hispanic/other. The majority of the black kids acted like animals on a daily basis. White kids couldn't really learn too easily, and the black kids sure as hell didn't want to. School for kids who wanted to learn was a complete nightmare from K-9, until high school when the classes and curriculum were "tracked" into college preparatory, vocational, and "general" diplomas. There were a handful of black kids that had their shit together and were in the college prep track - one of which was our valedictorian and went on to become an accomplished doctor. There were a few other exceptional black kids like her, but the college prep track was about 95% white. The vocational track was about 50/50 - mostly FFA kids, trailer park sluts and jocks who weren't complete dolts, while the "general" track was a fucking zoo. If the black kids didn't drop out by 10th grade or so, they usually just tried to kill each other or any unfortunate white kids that happened to wander haplessly into that wing of the school building.

It's pretty hard not becoming a racist when you grow up in that environment. Every day serves to reinforce your confirmation bias. Luckily I managed to keep my head on my shoulders, mostly by keeping it down and never making eye contact. I took a few beatings from black kids and generally despised them, up until I moved to a suburban area north of the Mason-Dixon, where I encountered more black people who weren't howling ghetto jerkoffs, but rather contributing members of civilized society. I like to think that I'm not a racist now, but seeing shit like this brings back familiar negative emotions.