The report attends to the following question: How can we interpret pre-service teachers’ use of covariational reasoning when they explore and design spatial reasoning tasks for the primary mathematics classroom? Covariational reasoning has been broadly associated with quantitative reasoning and specifically associated with concepts such as variable and function, but it is also a critical aspect of spatial reasoning. Participants (N=7) engaged in task design sessions in Desmos, a dynamic geometry environment. I draw on discourse analysis (Sfard, 2008) to describe how they enacted covariational reasoning in their task exploration and design and discuss implications for pre-service teacher education.