In Sweden, the policy of national testing was expanded in 2013 by introducing national tests in science in the sixth grade. The aim of this study is to contribute knowledge about the enactment of this policy of national testing by investigating students' experiences of taking the tests. Students were interviewed about their experiences of taking national tests, and a narrative analysis was conducted. More specifically, the students' stories were analysed in terms of identity performances taking shape in relation to a testing discourse. The analysis shows a variety of aspects that the students themselves stress as important when taking the tests; such as the lack of time provided, difficulties regarding the actual tests, processes in the classroom context, and the importance of the test results for their grades. Several of the identity performances in the students' stories refer to a testing discourse stressing that teachers focus on testing procedures rather than caring for the students when the policy of national testing is enacted. The results also emphasize the difficulties in understanding the test questions as well as discrepancies in science content between what is taught in school and what is being tested.