This presentation focuses on how students and teachers at a university in Japan understand Project-Based Learning (PBL), what practices they see as central to PBL, and what puzzles come up for them as they do PBL. The background is a curriculum reform whereby an existing first- and second-year university research and writing programme is transitioning in 2022 and 2023 into PBL courses. In the new curriculum students will do at least three projects in one year where they identify and choose a problem in society that interests them, plan and do research, journal, and create a written product for each project - often using digital technology - to be published in a public forum beyond their immediate class. While students will, as now, do online research in each project, the new PBL courses will have a clear emphasis on students talking in each project with “close others” (other students, family members, people in local communities or local networks that students are part of). Other important differences and challenges will emerge as teachers and students experiment with PBL in 2022. From interviews, discussions, and written reflections, this poster presentation explores key learner development puzzles in teachers’ and students’ diverse PBL understandings and practices.