This paper looks at identifying deviations from the linguistic norm in self-description essays written by the fourth-grade elementary school students at the phonological, morphological and syntactic levels. The students' self-description essays were analysed, and the identified errors were divided into the following groups: grammar, lexical, stylistic, and spelling mistakes. Errors were then identified, listed, and explained. The research included the current generation of the fourth-grade students at Eugen Kumičić Elementary School (Slatina) and the earlier generation of the fourth-grade students at Grgur Karlovčan Elementary School (Đurđevac). The aim of the research was to identify and analyse linguistic errors in self-description essays written by the fourth grade elementary school students, and then compare the writing pieces written by the current generation of the fourth grade students (2020) with those written by the earlier generation of the fourth grade students (2001). The total sample consists of 377 linguistic errors in 60 examples of student writing. Spelling mistakes account for the most common errors among the earlier generation of students, precisely writing words with the letters č and ć, whereas the capitalization errors were the most common among the current generation of fourth grade students. Furthermore, both generations of students were equally prone to make syntax errors, while the current generation made more morphological errors. The earlier generation was more prone to make stylistic errors, while the lexical errors were more common among the current generation of students.