Contribution: A learning-by-teaching methodology through games can be used to promote informatics (computer science) in primary and secondary education. Applying the proposed activities can change students' perception of informatics from seeing it as merely using computers to seeing its relationship with mathematics. The experience can also help students acquire competences in teaching. Background: Although students, specifically in primary and secondary education, are increasingly competent in terms of technology use, it has been found that in many cases informatics, as a science, has been relegated to a secondary status; it is usually considered only as a tool or additional resource, and not as an object of study. Intended Outcomes: To refine the application of the learning-to-teach-to-learn (L2T2L) methodology, a learning-by-teaching methodology that has students learn and then, in turn, teach that learning to younger students, in cascade from university to secondary to primary students. To analyze its effects on students' attitudes toward informatics. Application Design: The model incorporates a learning-by-teaching approach in a multistage sequence across different kinds of learners and teachers, using fun, game-like materials. Findings: The use of the action research methodology allowed adjustment of the educational methodology, providing more reliable data and enough experience to suggest how to extend the project to a broader audience. Although the results obtained were less significant than expected, the experience did give students a more realistic view of informatics.