In this presentation the results from a study where two separate test forms in mathematics, one paper-based and one digital, were administrated to two groups of students will be reported. The aim with the study was to learn more about differences in difficulty if mathematics items are served in a paper and pencil form or if they are administrated digitally where also the answers are given digitally. A second issue investigated was the cognitive workload and the use of scratch paper. The hypothesis was that when solving short answer items digitally students only use mental arithmetic and not the scratch paper and that a possible lack of scratchpaper use might affect the proportion of students solving the item correct. A third issue is about writing down solutions to mathematical problems using an equation editor, which will be necessary when the national tests are digitalised in a couple of years.