I for one didn't mention black kids doing worse in school however I'll rephrase what I did say. The idea that black people commit more crimes is cemented in jokes and films and general conversation. If a Black kid gets treated badly by police there are responses of "maybe blacks shouldnt commit so much crime"
Yet in your link and mine below, all we can see is that black people get arrested and convicted more. Why is that? Black people are just inclined to crime? Systemic factors intersect to make crime more likely amongst Black people? Inequality in the criminal justice system? A combination of factors?
On an experiential level you can speak to plenty of Black people who are innocent and get testimonies of how they are treated as criminals or misbehavers in ways their non-Black peers are not.
Where does this come from? Can you securely say this does not, in any way, stem from the criminalisation of black people that occured after emancipation? When innocent black people are labeled as thugs, where does this come from and does this stereotyping not have an impact on how the criminal justice system tries black people today?
I think it's really reductive to look at the situation of black people and say conclusively that it is solely a result of our own doings. Even amongst black people you can hear people say "black people are quick to blame everyone else but ourselves" and whilst I would never say no black person has ever done anything wrong, we are all faultless as a race, do not accuse any individual black person of anything, It's true that systemic oppression is real, it stems from colonialism and slavery and has a very real impact on the lives of black people today to an extent where it IS more difficult for middle class, achieving, non-criminal black people to succeed.
m.huffpost.com/us/entry/black-crime-rates-your-st_b_8078586.html