In the context of this article, we wonder about the possibilities that a teaching sequence, based on citizen science and implemented in class by a teacher and his students, can keep a form of authenticity, even though the students have never met or communicated with the scientists carrying out the project. Our study is based on the constructs of authenticity and teaching practice. Data is collected from video recordings of class sessions. The results show that teachers, because of their didactic and pedagogical choices, can recreate a disciplinary authenticity reinforced by an epistemological authenticity.