We aimed at investigating knowledge revealed by the tutors of a continuing education course for mathematics teachers offered at a distance. Initially, we observed the work of 32 tutors over a year, in order to typify their interventions in discussion forums with course participants. From the results, we offered training to a new group of tutors, in order to improve actions that we considered were below our expectations. Between August 2012 and July 2013, we observed six tutors who are the subjects of this research. An adaptation of the Technological Pedagogical Content Knowledge (TPACK) theoretical framework was used in their training. This qualitative research made use of the observation of the tutors' work, which was analysed by means of discursive typologies found in tutors' interventions in discussion forums. Our analysis indicated that affective and attitudinal components play a key role in tutoring in this context.