Every subject has its own language – patterns of linguistic features of expository texts in German stem textbooks

• Some linguistic features can inhibit students’ text comprehension. • Texts of STEM subjects have their own pattern of prevalent linguistic features. • Expository texts in chemistry textbooks have the highest linguistic complexity. • Expository texts in mathematics textbooks have the lowest linguistic complexity. • Practical implications for STEM teachers are suggested and discussed. STEM education relies heavily on written language that students need to process in order to understand expository texts in the school context. Prior research indicates that students are challenged by certain linguistic features (LFs) prevalent in expository texts. Therefore, it is important that teachers support students adequately in their comprehension process. For German textbooks, however, research that examines which LFs are prevalent in which STEM subject is missing. In this study, we exploratively analyze the patterns of LFs of different STEM subjects (biology, chemistry, geography, mathematics, physics). For this, we examined 398 German texts extracted from 32 secondary textbooks. We found that some LFs are more prevalent in certain STEM subjects than in others. The found patterns of LFs hold the potential to provide concrete starting points for teachers to adequately support their students in processing the LFs of their respective STEM subject. Further implications and limitations are discussed.