Co-design of learning environments, with explicit accounting for the sociohistorical underpinnings of educational inequities and disparities in America, has been missing in Universal Design for Learning (UDL) discourse and implementation. Accordingly, UDL has primarily accounted for the interactions among micro-level (individual) variables, while disregarding their dynamic interaction with macro-level (structural) variables. This paper calls for greater use of participatory design and critical theory understandings of UDL implementation to promote a co- designed learning environment model, rather than a teacher-centered design model.