„In Canada, Chile, Denmark and Hong Kong (China), 15-year-olds spend five hours per week in language-of-instruction classes, while students in Austria, Finland and Russia spend less than 2 hours and 30 minutes per week in these classes.“
OECD (Hrsg.), „PISA 2015 Results (Volume II): Policies and Practices for Successful Schools (2016), S. 43