Dealing with socio-scientific issues, SSI, entails emphasizing classroom practices in which multiple sources of knowledge and diverse perspectives on the issues, including the students’ views, are explored. Such classroom practices aim to empower students to participate in decision-making on SSI. This can be accomplished by enhancing the students’ independence as learners and positioning them as legitimate participants in societal discussions on SSI. At the same time, it has been reported that teachers find it difficult to interact with students in ways that promote the students’ independence as learners and encourages them to voice their perspectives, while pursuing intended learning goals in terms of a predefined body of content knowledge. However, detailed studies on teachers’ interactions with students when dealing with SSI are scarce. The present study aims at providing knowledge of characteristics of teachers’ interactions with students that are relevant to the positioning of students in the SSI classroom. Data consisted of transcripts of audio-recorded interactions between an upper secondary school science teacher and six student groups dealing with a SSI on climate change. Positioning theory was used as a lens to analyze the transcripts with respect to the following research questions: 1) How are the students positioned as participants in the classroom? 2) How are the students positioned in relation to the issue under consideration? The results show that the teacher-student interactions supported or undermined students’ empowerment by making available or delimiting different positions for the students as participants in the classroom and in discussion and decision-making on SSI. The different positions sometimes align with disparate educational aims. Consequently, knowledge of how the teacher-student interactions functioned to position the students is suggested to support teachers to promote students’ pursuit of intended educational outcomes when dealing with SSI.