The purpose of this study was to know the perspectives that a group of teachers from the state of Sonora, Mexico, have on online training and on themassive open online courses(MOOCs)"Key Learning Collection". These MOOCs were designed to make basic education teachers aware of the approaches of the new educational model derived from the 2013 reform. The approach applied in the research was the qualitative one; the data was collected through semi-structured interviews with six primary school teachers. Teachers' perspectives regarding online training focused on the categories of analysis: online versus face-to-face in-service teacher training, participation requirements of online in-service teacher training, and challenges of online in-service teacher training; and regarding MOOCs, they were categorized into: didactic-pedagogical dimension of the courses, massiveness and absence of tutor, implemented technological infrastructure, and the role of the school authority for its implementation. The findings show an open position of teachers towards online training;,however, their willingness to participate in it is influenced by their previous experiences in this modality. Likewise, the findings highlight the need to promote a joint commitment, both of educational authorities and teachers, to successfully implement massive teacher training strategies such as MOOCs.