„Proportionately more private school teachers have obtained degrees from high-ranking universities and earned good grades; more also have a post-graduate qualification, and more are specialists in maths and sciences, typically the subjects where teachers are in short supply. Private school heads are also increasingly successful at attracting experienced teachers from state schools; this matters because teachers’ skills develop considerably over the first few years in the classroom.“
Univ.-Prof. Dr. Francis Green u. a., Engines of Privilege (2019), S. 100.