Specialized learning support software can address the low societal participation of low-literate Dutch citizens. We use the situated Cognitive Engineering method to iteratively create a design specification for the envisioned system VESSEL: a Virtual Environment to Support the Societal participation Education of Low-literates. An initial high-level specification for this system is refined by incorporating the societal participation experiences of low-literate citizens into the design. In two series of user studies, the participant workshop and cultural probe methods were used with 23 low-literate participants. The Grounded Theory method was used to process the rich user data from these studies into the Societal Participation Experience of Low-Literates (SPELL) model. Using this experience model, the existing VESSEL specification was refined: requirements were empirically situated in the daily practice of low-literate societal participation, and new claims were written to explicate the learning effectiveness of the proposed VESSEL system. In conclusion, this study provides a comprehensive, theoretically and empirically grounded set of requirements and claims for the proposed VESSEL system, as well as the underlying SPELL model, which captures the societal participation experiences of low-literates citizens. The research methods used in this study are shown to be effective for requirements engineering with low-literate users.@en