[Objective] This study is intended to characterize the mathematical work of secondary education students in technical-professional education (TP), who participate in a didactic program that integrates mathematical learning and a specialization in administration. [Methodology] This is a qualitative investigation based on a case study that analyzes mathematical work in the classroom by students in the final year of their TP education. The theoretical foundation considers aspects related to interdisciplinarity and the theory of Mathematical Work Spaces. [Results] Results of this investigation show the distance between the analyses expected and what the students actually did, which is expressed in the presence of the [Sem-Ins] plane above the others. Student results were organized according to the type of answers they provided: standard, incomplete, and blocking or difficulty. [Conclusions] Results of this investigation showed that the first sub-task was carried out in a standard manner with activation of the [Sem-Ins] plane and in a part of it the discursive genesis, while the results of the following sub-tasks corresponded to incompletion and blocking or difficulty, respectively, in which only the presence of the semiotic genesis was observed. Finally, it can be concluded that knowledge of the concepts of the specialization were not an obstacle when they were related to mathematical work. However, from a mathematical perspective, difficulties were identified with respect to the communication of discursive reasoning, associated with discursive genesis and the interpretation of graphs, which suggests the need to work on activities that integrate mathematics with the TP area of specialization – in this case, administration.