Classrooms in the United States are increasingly becoming “linguistic contact zones” (Cazden, Kwek & Comber, 2009, p. 1), where students’ language varieties coexist with schools’ dominant English discourses. However, students’ full linguistic repertoires are rarely recognized as resources in academic spaces that continue to rely on English as the dominant medium of instruction (García & Flores, 2014; Menken & Kleyn, 2010). In our study, we explore dynamic language practices of emergent bilingual students during cross-age peer tutoring interactions within officially designated monolingual instructional settings.