This chapter reports on a research project in which a group of students in pre-school teacher education participated in an educational intervention based on the development of process-based assessment. A didactical design was developed and structured into three phases for supporting students in building formal knowledge from their prior informal knowledge. Moreover, the design was implemented in an online context that facilitated documentation and reflection. A qualitative approach was taken that aimed to understand the learning environment emerging from the didactical design through the use of technology by addressing questions about the teacher's role, the learning process, and the assessment process. Data was collected through in-depth interviews and a questionnaire, which were analyzed through inductive thematic analysis. The concept of variation was used in the analysis of the student perspective on the didactical design. The results indicate how the concept of variation was helpful in highlighting the underpinning affordances and constraints of this environment and the associated social relationships.