Validation of the Classroom Assessment Scoring System in Inclusive Upper Elementary Classrooms in Switzerland

ABSTRACT A high interaction quality is the cornerstone for successful academic and socio‐emotional development in children. The Classroom Assessment Scoring System (CLASS) is a reliable and valid tool to develop high‐quality interactions in regular classrooms across cultures. The current paper aimed to study and to extend the reliability and validity of the CLASS‐Upper Elementary version (CLASS‐UE) to inclusive upper elementary classrooms in Switzerland, using data of co‐teaching teams from 64 Grade 3–6 classrooms across 14 cantons. Results showed good to excellent interrater reliability (IRR) across different measures for IRR. Furthermore, a multi‐level confirmatory factor analysis indicated a good fit of the theoretically proposed three‐factor structure, with some modifications (e.g., cross‐loading). These results are promising with regard to developing interaction quality in inclusive classrooms.