Developing a Validated Test to Measure Students’ Progression in Mathematical Reasoning in Primary School

Not enough effort has been invested in developing reliable and valid assessment instruments to measure students’ development of reasoning competences in mathematics. Previously developed tests relymostly on standardized multiple-choice assessments, which primarily focus on procedural knowledge and rote learning and not on how students argue for and justify their results. This study reports on the process of developing a test to assess students’ reasoning competence in primary school classes and on the statistical results of a verification study. The test is based on item response theory (Rasch model) and was used in a largescale mathematics intervention project about inquiry-based teaching. The data was collected from 5,516 primary school students in Denmark. Data analysis indicates the test has satisfactory validity and reliability, but the test was still unable to measure statistically significant progress at the intervention schools.