Bit:chat: A Tangible Approach to Teach Children about Everyday Secure Communication and Cryptography

As digital communication has become integral to children’s social interaction, they must understand when and how their privacy is protected. This paper presents the design and evaluation of Bit:chat, a tangible tool that introduces children to secure communication and cryptography through hands-on collaboration, by combining networked micro:bits, a web interface, and paper templates. Drawing on constructivist and collaborative learning, Bit:chat externalizes client–server communication and cryptographic processes into physical artifacts and actions that children can explore and manipulate. Bit:chat was evaluated in an exploratory study in a K–9 classroom setting, and qualitative results illustrate how the tangible design supported engagement, peer collaboration, and exploratory learning. Quantitative results further show improvements in children’s understanding of core concepts of secure communication. We reflect on how tangible approaches can help children connect abstract cryptographic concepts to the technologies in their everyday lives and discuss the challenges and opportunities for designing such tangible tools.