Probabilistic language is a main component in the teaching and learning of probability; however, research analyzing probabilistic language in textbooks, which are fundamental didactic tools, is scarce. Consequently, in this research, we studied the various probabilistic languages used in Spanish secondary school textbooks. We performed a detailed content analysis of two complete series (grades 1 to 4; the last with two options) of Spanish prestigious editorials published after the last curricular guidelines in 2022; 10 books in total. We researched the verbal, symbolic, tabular, and graphical language in each textbook. Results suggest differences in the way each editorial introduces its everyday and probabilistic language. Although the number of new symbols is small, some of them are complex or used inconsistently. There is scarce use of tables and graphs, except for tree diagrams and two-way tables, in the study of conditional and compound probability. We conclude with recommendations to improve probabilistic language in textbooks and facilitate the learning of probability in secondary education in this way.
Batanero et al. (Wed,) studied this question.