Abstract Computational thinking is an ability that has been considered essential for people living in a society mediated by technology. This ability can also be helpful to people with little or no experience with technology, for practicing basic Computational Thinking skills may help understanding how a technological device works and can be used. However, to the best of our knowledge, little research has addressed Computational Thinking and its relation with Digital Culture, especially for reducing the digital divide. In this article, we draw on the notion of Mental Models to relate Computational Thinking and Digital Culture. We claim that practicing basic Computational Thinking skills when exploring simple prototypes favors building Mental Models that are useful to understand and progress in the usage of technologies, contributing to developing a Digital Culture. To situate our discussion, we present a case study that engaged adults, in their initial stages of literacy, in activities that grew from basic ones, with a low-fidelity ATM prototype, to more complex ones with a functional ATM prototype. Evaluation methods used were voting, feedback, structured observation and unstructured interviews. Results suggested our approach is promising as participants gained confidence and increased autonomy as the activities progressed, using the experience and knowledge they obtained from previous activities to perform the next ones.