Textbooks and reading books for the Croatian language are an important didactic tool that teachers and students use every day in class. For this reason, their content and structure are important, that is, the methodological templates and methodological instruments they contain. Since the textbook or reading book is the basic school book in the teaching of the Croatianlanguage, it must be evaluated according to the principles derived from the theory of didactic transfer and the theory of textbooks, before being used in classes. The subject of this paper's research is the tasks performed by methodical instrumentation. These tasks must prepare students very carefully and precisely in order them to learn to independently question the contents they are exposed to, but also to build their own knowledge. The aim of the research was to determine whether fourth-grade primary school textbooks for the Croatian language subject are designed to encourage the development of reading literacy, and whether there is a significant difference between the tasks in the textbooks of the three most represented publishers in the Republic of Croatia - akolska knjige, Profil Kletta and Alfa. The research resulted in positive results, in which a complete curriculum reform is visible, which also influenced the improvement of the textbook sets, specifically the textbooks and reading books that were analyzed. It was confirmed that the analyzed didactic tools were designed with the aim of encouraging the development of reading literacy, containing tasks of all levels to encourage the development of reading literacy in students. In addition, the research confirmed the absence of a difference between didactic tools published by different publishers, or more precisely, in the representation of tasks that encourage reading literacy among students in the fourth grade of primary school education.