„All research shows that families are extraordinarily important for student achievement. This is widely recognized, and underscores the fact that existing achievement gaps – by income and by race – cannot be looked upon as a simple reflection of differences in school or teacher quality.“
Univ.-Prof. Dr. Eric Hanushek, „School human capital and teacher salary policies“. In: „Journal of Professional Capital and Community“, 2016, Vol. 1, S. 24