Black African immigrants tend to be the best and the brightest of their countries—and therefore not at all representative of the “average” African.
In Nigeria, for example, there are two main options for bright kids—join the government or flee the country.
I have to wonder though, if many Africans are better centered than black Americans. Regardless of their station. It seems many children go to good schools that expect good behavior, and they are for poor children as well as wealthy. They may be shacks, but they get good education there.