Earlier, I said that my preferred approach is individualism. To understand this approach, try this thought experiment: imagine if everyone suddenly were afflicted with group-identity amnesia.
Group-identity amnesia would mean that each person would forget his or her own ethnic identity. It also means that we forget how to identify and interpret all of the markers of race or ethnicity. I would meet someone named "Cohen" and not think, "Must be Jewish." I would see someone with black skin and not think, "Ancestors must be from Africa."
It seems to me that a society with group-identity amnesia would have no reason to feel awkward about testing people for aptitude. It would have no reason to feel awkward about identifying individuals with different aptitudes. It would have no reason to feel awkward about placing some people in remedial classes and others in classes for gifted students.
Please read the whole essay before commenting.
Also, on a similar subject, there are columns by Will Saletan here and here.