The purpose of this study was to examine the impact of teaching based on the teaching-learning cycle on students' argumentative writing, with a particular focus on text structure and genre-specific features. The study was conducted with ten students in grade five at a Swedish primary school. The research questions focused on how teaching through the teaching-learning cycle affects students' use of text structure and genre-specific features in argumentative texts, as well as what changes could be identified before and after the intervention. The study was based on genre pedagogical perspective, the sociocultural theory of learning, and a modified version of Stephen Toulmin's argumentation model. An intervention design was used where students completed a pre-test and a post-test. Between the tests the students participated in teaching based on the four phases of teaching-learning cycle. The collected material consisted of 20 student texts that were analysed quantitatively using an analysis matrix focusing on thesis statements, arguments, counterarguments, development of arguments, conclusion and persuasive appeals. The result showed a clear development in the students' argumentative writing after the intervention. The post-test texts contained more clearly expressed theses, more developed arguments, a greater use of counterarguments and rebuttals, and more explicit persuasive appeals directed at the reader. The findings indicate that explicit and scaffolded teaching through the teaching-learning cycle can support students' development of argumentative writing and increase their understanding of argumentative text structure and genre-specific language features.