Thank you--but the thing that I don't understand is whether you are simply reading out the effect that Super Mrs C is talking about.

If some black children actually do hear far less language at home (or less directed at them in an interactive way where it's easier to learn), and/or are read far fewer books, then wouldn't you expect them to sometimes present with ELL-like characteristics?

"Black culture is comparatively unsupportive of the development of black kids' language skills, but schools can detect this and help fix it" isn't an argument against fixing the culture--it's an argument to fix that aspect of the culture so you don't have to rely on public schools which are, alas, not always stellar.

So if you're actually disagreeing with Super Mrs C, you need to have some other idea in mind for why black children are presenting with ELL-like characteristics. For instance, do you think that the dialect at home is so different from the school dialect that even with the linguistic plasticity in young minds, it can be too big a gap to fill without explicit instruction? Or that some other systematic difference in the school you were talking about (e.g. poverty rates often differ) is causing the same thing (in which case it's probably not just black kids who should be considered for ELL training, but anyone who has that difference)?

The reason I was confused is that it seemed to me from your tone that you were disagreeing, but your evidence seemed consistent with her take.