The crisis generated by the pandemic of the new coronavirus exposed some failures in education and the need to transform the reality of those involved, with a view to facing the barriers created by remote teaching, leaving a clear sign that it is necessary to use technology as an ally to educate in any place and circumstance. Thus, the present work aims to discuss the use of technologies in the teaching of Mathematics and to reflect on the preparation of the Mathematics teacher regarding the use of technologies in their pedagogical practice. A case study will be presented, using the GeoGebra software in a high school class. At the end, a proposal for a GeoGebra software workshop for Mathematics teachers will be presented, as an example of the potential of the use of technologies as auxiliary tools in the teaching of Mathematics.