„Across OECD countries, immigrant students who speak the language of instruction at home are roughly a half‐year of learning behind their non-immigrant peers in maths, while immigrant students who do not speak the language of instruction at home are about a year behind. These students are at an even greater disadvantage when it comes to reading.“
EU-Kommission (Hrsg.), Investing in our future: quality investment in education and training (2022), S. 25.