Research shows that the textbook has a central place in teaching of mathematics. Skolinspektionen (2009) states that mathematic teaching is "heavily controlled by the textbook" (Skolinspektionen, 2009, p.9). Johansson (2006) believes that it is important to increase the awareness of the textbook and its use in teaching of mathematics. The purpose with this study is to investigate teachers' use of textbooks in mathematics in the area of subtraction. The purpose is also to find factors that influences the teachers’ use of the textbook. The method chosen was qualitative interviews with eight teachers.

The results from the study confirms that the textbook has a central place in mathematics teaching. However the results shows that the use of the textbook varies between teachers. One of the teachers is working textbook bound and work exclusively with exercises from the textbook. The students will only meet the mathematics areas that are included in the textbook. The rest of the teachers are working with the textbook as the basis.  The textbook is offering organization to the subject. However, these teachers also use other sources in their teaching. One of the teachers who are working with the textbook as the basis are working with subtraction apart from the textbook. All these teachers mention a similar way of how they work with subtraction. They start with using concreate materials and let the students discuss strategies together, followed by individual work. A majority of the teachers express a desire to work more freely from the textbook but time limits and uncertainty prevents them. Some consequences of working textbook bound and with the textbook as the basis is discussed in this work.