Some teachers consider didactics of mathematics to be mechanical and this makes them to indiscriminately and irrationally employ techniques that are recommended in some contexts and not in theirs. One of the didactic methods that have become ritualistic in didactics of mathematics is group discussion. The controversy is the positioning of group discussions during lesson delivery. Improper positioning of good didactic method has a negative outcome. The qualitative methodology research was carried out with eight students of a teachers’ college. The informants were purposively selected. They were observed delivering lessons and then interviewed about their experiences in employing group discussions in didactics of mathematics. The data were analyzed using the Johnson-Christenson method. The results show that the student teachers employ group discussions ritualistically, adhering to technical rationality which stems from their educational significant others. It is hoped that the lectures will make student teachers to be aware of the essence and positioning of group discussions in didactic situations.

Keywords: Group discussions, didactics of mathematics, technical rationality.