This article-based dissertation examines students’ constructions of social and linguistic participation and social belonging in a linguistically diverse upper secondary classroom in Sweden. The focus is on a group of second language learners and their meaning-making processes in literary book-group discussions in a combined practice of the two parallel school subjects Swedish (SWE) and Swedish as a Second Language (SSL). SWE and SSL are two distinct school subjects in their own right, with different subject curricula and required teacher qualifications. In this dissertation, combined practice entailed SWE and SSL students being taught in the same classroom by a teacher who was qualified to teach both subjects based on the two curricula. The four key participants in SSL had migrated to Sweden due to outbreaks of war in their home countries. The theoretical framework consists of contact zone theory, including safe houses as safe spaces, dialogism, and transactional theory. A common denominator in these underpinnings is the notions of negotiation processes and power structures. Methodologically and onto-epistemologically, this dissertation is anchored in linguistic ethnography, which presupposes that research participants are co-constructors of data and meaning, and that linguistic analyses of interactions in local contexts contribute to discussions about social change at large. Article I focuses on three different learning spaces that the students in SSL had to navigate as part of their second language learning: whole-class, separate SSL group, and literary book-group discussions. Based on the findings of Article I, where literary book-group discussions seemed prominent for negotiations of meaning, Article II concentrates on one student’s trajectory of participation in a series of book-group discussions, and Article III centers around a particular group of students in SSL and their reflections on grouping strategies, participation roles, and discussion topics. The findings from these three articles show that student mobility between different layers of contact zones and safe houses seemed to provide an incentive for social and linguistic participation and social belonging over time. The findings also show that the four key participants in SSL seemed to avail themselves of social and linguistic participation and social belonging through an agency of vulnerability in literary book-group discussions as both contact zones and safe houses. This dissertation contributes to further empirical and theoretical discussions about developments of contact zone classrooms in Sweden and beyond, including the problematization of what teaching and learning in contact zones entails for students and teachers in this age of forced migration.