This PhD thesis was set to examine newcomer teenagers’ identity as learners of mathematics and English as an Additional Language (EAL) in the context of their transition into the Canadian educational system. Drawing on Ivanič (1998) who suggests a four-part model for the conceptualization of identity as a co-constitutive multi-dimensional framework, and addressing Ricoeur’s (1992) etymological distinction between idem and ipse (identity as sameness and identity as selfhood), a research design was set up to allow for an exploration of newcomer teenagers’ identity as learners of mathematics and of English as an Additional Language (EAL). The theoretical framework of this study draws on Ivanič’s (1998) four identity-related dimensions of (a) autobiographical identities, (b) authorial identities, (c) discoursal identities, and (d) socioculturally available selfhoods. The research design comprised three sets of data collection through family and individual interviews and focus group discussions. Following a dissemination of a Call for Participants, six families who have recently emigrated from Israel to Canada expressed interest to participate in the research. In total, six sessions of 90-minute family-unit interviews, 16 sessions of 90-minute individual interviews, and two sets of all-parent and all-teenage focus groups lasting 90-minute each yielded 26 interviews of over 39 hours. Data were organized according to the four identity-related dimensions that are developed in the theoretical framework of this study. Multiple, iterative rounds of analyses were conducted to first examine how identity is formulated in and through each of the four dimensions identified in the research literature and later explore the inter-relationship between the four identified dimensions and emergent themes. Findings reveal that teenage newcomers’ identity as learners of mathematics and EAL is multifarious, multidirectional, and inter-animated. While the teenage newcomers struggle with their developing identities as speakers of EAL and learners of mathematics in a new educational system, their collective identity as Israelis who make it against all odds, their developing stances in relation to EAL and mathematics, and the socioculturally available selfhoods draw a complex picture that depicts identity work in its making. Given the findings, the study adds to our understanding of the multifaceted and multidirectional nature of identity as crucial in the learning of EAL and mathematics among teenage newcomers.