Additive-Manufacturing-Processes, such as 3D-Printing, are commonly used in the automotive and aerospace industry. While most architectural building processes still involve the same design strategies and materials, the studio "Additive Circularity" combined the benefits of 3D-Printing with circular design strategies through modularity and interlocking concepts. The students explored the topics of 3D-Printing and digital design techniques in connection with circular design principles with sustainable materials. The modular design integrates sustainable thinking for reusable components which we can realize using large-scale 3D-Printing. Within the curriculum, the students explored in a smaller scale, how to create interlocking joints for building components starting from a physical form exploration, and combining them to form units, which can then be assembled into architectural structures as a building system. Throughout the course, modular design, structural concept development, visualization, and presentation workshops were held to support the students' skills.