Despite the extensive research on translanguaging in bi/multilingual classrooms, research on the context of first language (L1) classrooms remains scarce. This study fills the research gap by examining how a translanguaging space was created in an L1 classroom to prepare students to inhabit a world with different linguistic and cultural practices. The data were based on a linguistic ethnographic project in a first-grade L1 English Language Arts classroom in the U.S. Multimodal Conversation Analysis and Interpretative Phenomenological Analysis methods were employed for data analysis. This study revealed that such a translanguaging space encouraged students to view diverse languages as resources and appreciate linguistic and cultural diversity in the community. The teacher's ability to create a translanguaging space for her L1 English students was shaped by the pedagogical translanguaging knowledge gained from her teacher training programme. As such, we posit the significance for all pre- and in-service teachers to acquire knowledge of translanguaging to develop students' social-emotional well-being and their identities as citizens in this multilingual and multicultural world.