In-school vs. non-school factors

From How to fix our schools, in which Richard Rothstein, of the Economic Policy Institute, critiques Joel Klein’s and Michelle Rhee’s approach of focusing only on firing incompetent teachers as a means to improve schools:

“Differences in school quality can explain about 1/3 of the variation in student achievement. But the other 2/3 come from non-school factors.” In-school factors go beyond teacher quality: school leadership, curriculum quality, teacher collaboration. Non-school factors include economic consequences of parental underemployment, such as geographic disruption, malnutrition, stress, poor health.