This study focuses on how teaching is affected when two cultures meet: the Sámi culture, represented by the "lávvu," and the culture of teaching mathematics in a school. It describes the use of the "lávvu" (a Sámi temporary dwelling) as a classroom for teaching mathematics. For several years, and in cooperation with researchers, the teachers at the Guovdageaidnu Lower Secondary Schoolg have been developing interdisciplinary teaching content related to Sámi traditional knowledge. The findings of this study describe how tenth-grade students taught younger students. The empirical data used in this study originated from students' teaching in "lávvues" and consisted of audio recordings, field notes, and notes from conversations between the authors. The teaching was carried out at another Sámi school for students of the same age and younger. The organization of the teaching and the teaching itself can be seen as a hybrid of Sámi child rearing and the ordinary teaching occurring in Sámi schools in Norway.