Abstract
Studies have shown that a set mathematics textbook chosen by teachers is the dominant resource in mathematics classrooms in Australia and many countries throughout the world. The textbook exerts a strong influence on both content and pedagogy. In this study, a method of analysing textbooks was developed and applied to three middle years mathematics textbook series. The method was based on two pedagogical principles related to deep understanding, namely connectedness and structure and context, and focused on mathematical ideas based on proportional reasoning. The study found that the textbooks provided little support for the pedagogical principles. In most cases, the textbooks presented a specific procedure for each problem type, with little or no recognition of similar structures in different problem contexts.