This research considers the need to train teachers who can effectively integrate technology for teaching and learning mathematics. The primary goal of this research is to showcase a successful training experience by identifying and describing some indicators of the technological pedagogical content knowledge acquired by pre-service early childhood education teachers during their participation in this initial training programme. Specifically, we focus on the different ways of representing mathematical concepts and the mathematical processes that can be activated by including such modes of representation. The participants in this research were 28 PECTs, who were organised into groups that planned a set of tasks using technology to teach geometric concepts. The results show that the groups employed a variety of modes of representation, translations and transformations (connections), fostering the emergence of different mathematical processes. Thus, our proposal to integrate technology was satisfactory in this sense, suggesting its potential applicability across diverse subjects, particularly those in which the ways of representing concepts play a relevant role. Also, the analysis conducted may be extrapolated to subjects others than mathematics.