[najirama]

Not so fast.

It seems you haven't even taken the time to follow your own proposition (Intelligence, especially as operationalized by standardized testing, is as biological as height and athleticism.) to its logical conclusion; for if you had, you wouldn't have followed it with the statement, If I were a teacher in DC and the majority of my students were not from middle+ class families, I would quit ahead of time...

Last I checked, "middle+ class" wasn't a genetic trait. So either you misunderstand what 'biological' means (dubious), or you yourself cannot separate intellect/scholastic achievement from environment/socio-economic class.

If it is the latter, then you directly contradict your proposition about the biological immutability of intelligence. If it is the former, perhaps you can clarify what you really meant when you wrote biological.