„Over one year of schooling (and age), the proficiency of disadvantaged children increases at least as much as that of children from more advantaged families (who tend to be more proficient to start with). Schooling, in other words, does not reinforce pre-existing inequalities and may instead contribute to reducing socio-economic gaps.” (ibidem, S. 25)
Francesco Avvisati u. a., The learning gain over one school year among 15-year-olds (2021), S. 25.