Connecting university methods courses and teacher daily practice is a persistent challenge in teacher education. Another challenge is preparing teachers to enact equitable instruction that meets the needs of an increasingly diverse student population. We take on these challenges by supporting practicing elementary teachers to design case-based teaching scenarios for preservice teachers that engage them with enacting culturally grounded mathematics and science instruction. We draw on data from workshops with teachers to illustrate how the design process elevates teachers' voices while also supporting their own learning. Workshop features that proved powerful for teachers included collaborating with colleagues, offering and receiving peer feedback, and working with a table describing key features of culturally grounded pedagogy in mathematics and science.