Argumentative writing serves as a stage where students showcase their critical thinking, a skill they already possess and have cultivated throughout their lives. However, it is argued that learners need instances within the classroom to activate this thinking, enriching it under the guidance of their teachers. It is the teacher who shapes and adapts the pedagogical environment, enabling students to respond naturally and spontaneously to meet class objectives. In the upcoming chapter, the implementation of a didactic sequence designed to enhance the argumentation skills of Spanish as a Foreign Language (SFL) students. This approach provided opportunities for students to, through reading and writing, interpret situations, analyze messages, evaluate options, infer conclusions, take positions, and explain them, actively monitoring their argumentation and writing process. This strategy embodies active learning in an environment facilitated by the teacher, where students forge their critical thinking.