While existing literature has addressed teachers’ translanguaging practices in diverse educational settings, its integration into assessments remains limited. Adopting a participatory research design in the form of a teacher-research collaboration, the present study examined in detail how a content and language integrated learning (CLIL) teacher integrated translanguaging into a summative assessment in a Chinese immersion setting. I also delved into the perceptions of the teacher and her students regarding the assessment. The data were triangulated and included co-design notes, in-class and post-observation field notes, as well as transcripts of one-on-one interviews with the teacher and students. The findings show that the teacher skillfully integrated translanguaging, including using planned strategies and leveraging students’ full linguistic repertoires into the summative assessment. The concept of juntos (García, Ofelia, Susana I. Johnson & Kate Seltzer. 2017. The Translanguaging classroom: Leveraging student bilingualism for learning. Philadelphia, PA: Carlson), a collaborative dynamic among teachers and students appeared to play a major role in the assessment. Integrating translanguaging into the assessment appeared to render complex topics more comprehensible and relevant to the students’ lived experiences. Additionally, it is evident that the teacher–researcher collaboration deepened the teacher’s pedagogical practices in translanguaging and garnered positive feedback from students, indicating an increase in confidence, engagement, and the strengthening of their multilingual identities. I conclude with a call for assessments integrated with translanguaging, transmodalities, and co-learning practices, aiming to transform evaluations into affirmations of students’ funds of knowledge in today’s socio-cultural-political context.