Durham, N.C.

NO one seriously disputes the fact that students from disadvantaged households perform less well in school, on average, than their peers from more advantaged backgrounds. But rather than confront this fact of life head-on, our policy makers mistakenly continue to reason that, since they cannot change the backgrounds of students, they should focus on things they can control.

No Child Left Behind, President George W. Bush’s signature education law, did this by setting unrealistically high — and ultimately self-defeating — expectations for all schools. President Obama’s policies have concentrated on trying to make schools