Part-time high schools function as an important safety net for marginalized students, including immigrants, who are often excluded from society and mainstream education. Since 2015, drawing on the participatory action research (PAR) approach, I have collaborated with a high school and a Non-Profit Organization (NPO) to develop an extracurricular activity called One World (Multilingual Exchange Club), which aims to create "ibasho" (places where one feels comfortable, safe, and accepted) for and with immigrant youth, given their high dropout rate. This article focuses on this collaborative practice and examines how the club has functioned as an "ibasho" among immigrant students. Given the value placed on students' voluntary engagement under the guidance of supportive teachers during extracurricular activities, immigrant students were able to nurture a space where they could be free from others' eyes, even temporarily. The space also had an elusive culture that validated students' transcultural and hybrid identities, languages, and experiences, which led to their empowerment. By shedding light on the possibilities of the indigenous Japanese concept of "ibasho" and its practice, scholars and practitioners in Japan and abroad can develop critical questions and reimagine mainstream education to nurture immigrant students' sense of belonging.