14 years ago, the American educationalists Valerie E. Lee and David Burkham published a highly noticed and controversial study titled “Inequality at the Starting Gate: Social Background Differences in Achievement as Children Begin School” (Economic Policy Institute 2002). The authors work with a sample of 16,000 children who entered US kindergartens in 1998 and 1999 and who had taken the ECLS-K entry test, measuring a children’s basic reading and mathematical skills. The authors showed that the social and economic background of a child was a reliable pre...