In his presentation, Aleksander Kocaj presented the first results from the 2011 nationwide IQB Federal-State (Länder) comparison of children with special educational needs (SEN) at the primary-education level. Under the title “Where do children with special educational needs (SEN) learn better? A comparison of school competencies at the primary-education level between regular and special schools”, the current state of educational research on the type of schooling for this particular group of students was the first topic of discussion. Because the measurement of competencies of students with SEN presents a serious challenge, the comparability of the competence tests for students with and without SEN at regular and special schools was examined and results on measurement invariance were explained. The effects of different types of schooling in terms of children with special needs at regular schools having significantly higher competence values than comparable students at special schools were discussed alongside possible explanations for this.