This article examines the methodological aspects of using the National Corpus of the Kazakh language in school-based Kazakh language lessons and analyzes its theoretical and practical significance. The study demonstrates the effectiveness of the national corpus in developing students’ communicative skills—namely, reading, speaking, listening, and writing—and in forming linguistic norms. It was identified that the corpus provides natural language data, enabling students to understand word meanings through text structure, observe the functions of grammatical forms, and distinguish stylistic and communicative features of speech. In addition, corpus materials help students master the structure of dialogue, use words accurately, and understand phraseological units. Regarding linguistic orientation, the corpus fosters learners’ research skills by enhancing their ability to independently identify language patterns, compare linguistic phenomena, and draw conclusions. The findings of the study show that the national corpus is an important tool for improving linguistic competence, developing speech culture, and strengthening research skills. The article focuses on two main directions—developing communicative skills and forming linguistic norms through the use of the corpus. The results confirm that systematic use of the national corpus significantly enhances students’ linguistic competence, speech culture, and research abilities.