Sight-singing and musical dictation are considered as complementary activities by different Ear Training pedagogues but, surprisingly, studies conducted with participants working individually were not able to find benefits of singing associated with dictation taking. This pilot study aims at observing the effect of a sight-singing, performed collectively before melodic dictation, on dictation results. We carried out an experimental study involving 54 students from three universities, who were tested in situations emulating Ear Training classes. The experimental group performed a collective sight-singing before the dictation, and the control group remained silent during the activity. Statistical analyses demonstrated that the experimental group had a significantly better performance on dictation than the control group, showing new data in relation to previous researches, that did not observe contributions of sight-singing related to dictation taking. We believe that collective sight-singing promotes cooperation between students, leading to better performance on reading than individual activities, thus improving dictation results. Although our pilot study counted on a small number of participants, remaining the necessity of future research expanding this one, it points to the potential benefits that collective activities could bring to the often-individualized instruction in Ear Training classes.