This book constitutes the proceedings of the 18th International Conference on Informatics in Schools: Situation, Evolution, and Perspectives, ISSEP 2025, held in Trier, Germany, during September 8–10, 2025. The 13 full papers presented were carefully reviewed and selected from 41 submissions. The papers cover the following topics: Curricula and Computer Science Concepts; Teachers’ Perspective; AI and Digital Literacy; Programming, Problem Solving, and Computational Thinking.