The practice of grading students’ knowledge is as old as education itself (Lundahl 2006). Yet, it has not been an issue of great concern in teacher education, nor in the educational sciences, until rather recently. This means that current knowledge is limited regarding questions such as how teachers decide upon a grade, the specific competencies needed for grading, the weight assigned by teachers to different aspects of student knowledge, the relationship to official demands on formal grading, and to what degree tradition and/or colleagues affect teachers’ grading. The first part of this presentation is concerned with research on teachers’ grading practices – i.e. the assessment data teachers use when grading – both from a historical and a contemporary perspective. The presentation draws on systematic research reviews and a reading of more than 6,000 peer-reviewed articles on the topic (Hultén, Klapp, Lundahl & Mickwitz 2015, Klapp 2016, Lundahl 2017), as well as on a recent empirical study investigating teachers’ rationales for awarding grades in English. The second part of the presentation reports from an interview study, investigating how grades and assessment data are used as a basis for making decisions about the provision of supplemental support in compulsory school in Sweden. Findings indicate that grades and assessment data are used differently depending on students’ difficulties. This means, for instance, that students with learning difficulties are identified and provided support with greater precision, as compared to students with behavioral or motivational problems.  

 Even if we recognise a growing body of knowledge on teachers’ grading, we also find that the use of grades as data by teachers and schools is basically a white spot on the research map. We have found some indications in the literature that curriculum and assessment-system designs have neglected the perspective of teachers, leading to a de-coupling between professional assessment practice and formal expectations on data use in grading and using grades as data.