The Critical thinking development is one of the main objectives present in the National Curriculum Parameters, as it is clear their intention of promoting teaching which is directed to the construction of citizens. Moreover, the work with argumentation is considered an important factor in the exercise of citizenship. We believe that the practice related to the identification or selection of arguments may be an excellent opportunity for the development of critical sense, if the teacher has some theoretical knowledge about the subject and uses an adequate methodology. Thus, The objective of this paper is to offer theoretical explanations and practical suggestions for the development the students' critical capacity on arguments choice or identification in text production.