This essay is a qualitative study that examines seven teachers ́ views on argumentative texts. The aim is to examine how teachers work and discuss argumentative texts, and how they work to develop students ́ writing. The main question is: What are the teachers experience, perception and attitude about working with argumentative text? Furthermore: What specific features are important when they mark this type of text? : How do teachers work with formative grading in terms of writing this type of text? Research shows that Swedish students ́ ability to write argumentative texts are inadequate. This study shows that teachers work varied and that they have a positive attitude to the subject. But it also shows that they focus on different abilities when they mark argumentative texts. Some teachers focus on linguistic correctness, while others focus on argumentation, which leads to different marking conventions on the same text. It is also noted that the interviewed teachers do not have a common language when they talk about argumentation, even though the essence is the same.