„Data from PISA 2015 show, for the 35 OECD countries that 15-year-old students who report higher exposure to IBSE (Anm.: inquiry-based science education) do not score higher in science than their peers. Worse even, in 25 of these countries, greater exposure to IBSE was negatively associated with science performance.“
Dr. Silvia Salchegger u. a., Explaining Waldorf students’ high motivation but moderate achievement in science. In: Large-scale Assessments in Education, (2021) 9:14, S. 3.