This thesis examines students’ work with mathematics textbooks in Year 1 (students aged 7–8 years) of Swedish elementary school. The aim of this thesis was to contribute knowledge about and an understanding of how students make meaning in their work with mathematics textbooks. Central to the thesis was the textbook’s designed meaning potentials, or the meaning potential needed to solve the exercise as designed, as well as the students’ meaning-making when working with the textbooks. With regard to the students’ meaning-making, interest is directed first, to the students’ specific meaning-making in the work with the textbook and second, to the students’ opportunities to take agency in the work with the textbook. This thesis was delimited to the area of subtraction in both printed and digital mathematics textbooks. The theoretical point of departure for this thesis was a design-oriented multimodal perspective (Selander & Kress, 2010). Interest was directed to the various resources for communication, or modes (e.g. Kress, 2010), in the mathematics textbook, such as images, mathematical symbols, moving images, writing and speech. Two studies were conducted: Study 1, Multimodal textbook analysis and Study 2, Students’ meaning-making. Two analyses were made in Study 1. The first was a descriptive textbook analysis mapping out the modes and subtraction in all Swedish Year 1 textbooks, totaling 17 textbook series, both digital and printed, and approximately 1,700 pages. That analysis was followed by a multimodal qualitative textbook analysis of 2–4 exercises from each textbook series according to its designed meaning potential. Study 2 examined the students’ work with mathematics textbooks. The data that formed the basis for the analysis were textbook pages, the teacher’s guides to the used mathematics textbook series, video material of 18 Year 1students’ work with these pages and representations in the form of studentresponses. The analysis involved a multimodal approach focusing on what mathematical content the exercises were designed to offer and what the stu-dents discovered when working with the mathematics textbook.Two articles were written based on Study 1 (Articles I and II), and two were written based on Study 2 (Articles III and IV). In addition to this, the data from Study 1 and the results from Study 2 were also analyzed using the concept of agency to further deepen the understanding of students’ meaning-making when working with mathematics textbooks. The results showed large differences between mathematics textbooks for Year1 in Sweden, regarding both how different modes are used and how subtraction is presented. The results also showed that the students’ work with mathematics textbooks differed. The students’ meaning-making was sometimes based on the designed meaning potential but sometimes not. Regarding images, the results showed that images could be particularly challenging for the students to interpret and that several students expressed that it was desirable to solve the exercises without using the images. The analysis using the concept of agency showed that exercises in which students could choose their working methods made it possible to take agency and that the students’ possibility for agency is affected by the prevailing notion that successful mathematics students do not use images but base their meaning-making on mathematical symbols. All in all, three conclusions were drawn. First, the mathematics textbook as a teaching resource could be developed, both printed and digital mathematics textbooks. Complexities can be detected more easily through greater awareness of modes as various forms of expression for the textbooks’ mathematics content. Second, the complexity of the students’ individual work with the mathematics textbook was highlighted. The students’ individual work should start from the basis of the exercise’s design, so that the students’ meaning-making can be directed to the designed meaning potentials. Third, for younger students to discover themselves as mathematical individuals, one must question the notions that mathematical symbols are the most important mode for young learners and that images are for those who find mathematics difficult. Based on these conclusions, questions can be raised concerning students’ potential for discovering themselves as mathematical individuals and whether the students’ self-discovery as mathematical individuals would differ if the mathematics textbooks more fully recognized students’ meaning-making using various modes. One question raised in relation to the students’ possibilities to take agency when working with mathematics textbooks concerned what knowledge is recognized in Year 1 mathematics textbooks. The results indicated that mathematical symbols already occupy a special position in Year 1. If modes other than mathematical symbols are more widely recognized as knowledge, then more young students will discover themselves as mathematical individuals.