„The results showed that students enrolled in gifted classes performed better academically and often needed less time to achieve certain curriculum milestones compared with students from regular classes in the same schools. The study showed, furthermore, that those gifted pupils who attended gifted classes did better than comparably gifted pupils who remained in regular classes. No substantial differences in noncognitive variables were found.“
Univ.-Prof. Dr. Albert Ziegler u. a., Gifted Education in German-Speaking Europe. In: Journal for the Education of the Gifted (2013) 36(3), S. 399.