This article reports a study on members in self-organised Facebook groups for teachers. The aim is to investigate how teachers' needs and actions form their roles in the extended staffroom. 26 teachers from six different Facebook groups within two different school subjects, mathematics and Swedish, are interviewed. The results reveal a trajectory from a lurking behaviour as authorised visitor to a key person within the community of the group or an influencer, where teachers can function as authorities in their field. In relation to this trajectory, the interviewed teachers describe the choice to become public as a crucial step, emphasising the courage needed. A next important step can be identified when teachers leave the role as consumers of content that others provide, asking questions and commenting on others' posts, in favour of a more contributing role, publishing their own posts and expressing an agenda. Further, these kinds of large Facebook groups can be seen as a node in teachers' social media networks.