This work aims to present a collection of activities aimed at developing writing and speaking skills in Mathematics classes for the final years of elementary school and for high school. The theoretical foundation presented promotes reflection on the interaction between Portuguese Language and Mathematics, the use of activities that encourage this interaction and aims to provide opportunities for the improvement of written and oral languages on the school floor. The reflection was based on the National Curriculum Parameters, the Common National Curriculum Base and scientific articles by authors who deal with this topic. The concepts and mathematical results used in the activities are defined or demonstrated in the work and serve as theoretical support for what is proposed. The analysis of the cited documents and the content of the theoretical framework points out that the interaction proposed here is possible, important and favors the development not only of oral and written languages, but also contributes to the appropriation of the mathematical concepts worked on and to the exercise of autonomy and criticality.