Abstract:
Among the key factors in textbook design are the readability of texts and adherence to the “simple to complex” principle. This study aimed to assess the readability of texts and examine the extent to which the simple-to-complex principle is followed in Persian language and literature textbooks for secondary education in Afghanistan. The research employed a descriptive and quantitative content analysis method, using the Flesch and Laflen readability formulas. The study population consisted of the texts of seventh-, eighth-, and ninth-grade textbooks, with samples randomly selected from the beginning, middle, and end sections of each book. Data were analyzed using descriptive statistical indicators. The findings indicated that the readability level of the texts is appropriate only for ninth-grade students and unsuitable for seventh- and eighth-grade students. Moreover, the simple-to-complex principle was not consistently observed either within the internal structure of the books or across different grade levels, and in some cases, the sequence of content was arranged from complex to simple. The results underscore the need for a scientific review in the authorship and organization of Persian language and literature textbooks for secondary education in Afghanistan.