Introductory electricity is a difficult topic for most lower secondary students, especially the development of an adequate conceptualisation of voltage is seen as a major obstacle. A few instructional concepts concerning the teaching and learning of physics have been proven helpful when it comes to constructing conceptual knowledge. For example, the choice of content structure, meaningful elementarisation of basic concepts or adequate use of analogies. What has not been in the focus is how physics school textbooks consider these factors. In this article, we compare four widely used Austrian physics school textbooks concerning their content structure, definition of basic concepts and their use of analogies. Results show that the concept of 'content structure diagrams' is a useful tool to analyse schoolbooks. Although Austria has a compulsory syllabus, the four schoolbooks greatly differ in the amount of covered content and interlinking of concepts. However, a few common approaches regarding the sequencing of the concepts were identified and are reported in this article.