Introducing Formal Verification with LEGO R ©

“In the end, you are a mathematician, not a computer scientist” or “Have we not already discovered everything in computer science?”. Which theoretical computer scientist has not heard a similar sentence when trying to explain their research to a layperson? Promotion of theoretical computer science, and formal methods in particular, is mainly hindered by the high level of abstraction commonly used in the field, and probably furthermore complicated by a lack of education of the people thereupon. We present in this paper an educational experiment intended to explain the importance and aim of formal methods, along with the challenges they present. It uses LEGO R © robots as an anchor to the real world, introducing fun into the presentation. Primarily targeting high-school students, it forms a solid and adaptable basis to reach various audiences.