The purpose of this study is to investigate, based on young adults' experiences of ensemble playing during their high school years, how widely gender is produced or reproduced and what role teachers have based on their experiences. This was achieved in a phenomenographic study with qualitative interviews used as a method for collecting data. The participants in the studies consist of young adults who have studied ensemble courses under the Swedish curriculum Lgy 11. The results show that the ensemble subject largely reproduces already established gender patterns as most of the ensembles already play gender-specific instruments when they enter high school. The study also shows that certain types of masculine and feminine behavior are found within these contexts when it comes to claiming space. The results indicate that the teacher has, in these contexts, an important role in offering space to all participants in an ensemble through norm-critical thinking and awareness of gender. The teachers who appear to work norm-critically in this study allow the students to change instruments with eachother in certain ensambles or encourage them to practice a secondary instrument that is not normally connected with their gender. In cases where the teacher does not pay attention to these patterns, the behavior is reinforced and creates a feeling of resignation among those involved who cannot claim their place in the group. But it can also be seen as a didactic quality to allow the students to work and develop the main instruments they have already chosen as there is not necessarily a desire among the students to play an instrument other than their main instrument just for the sake of crossing gender boundaries.