Due to the COVID-19 pandemic, educational institutions at all levels closed their doors and began to operate remotely. In this paper, we analyze the educational experiences of preservice mathematics teachers (PMTs) enrolled in mathematics teacher education programs from three South American universities, as the pandemic was unfolding. An exploratory study was conducted, based on an inductive and thematic qualitative text analysis of narratives written by 24 PMTs. Based on the study, we report on the following aspects: (1) experiences of PMTs in the passage to remote education (RE) mode (considering characteristics of remote classes-interactions, the rhythm of the class, teaching work-time management, home-classroom fusion, and physical and psychological discomfort), and (2) opportunities and limitation experienced by PMTs in relation to the use of technologies. The results of the study suggest the need to rethink teacher education programs regarding the integration of technologies in mathematics classes, the opportunities offered by hybrid education, and teacher education for distance teaching.