This document discusses the importance of developing teaching materials. It defines learning resources as any information or media that can help students learn as part of the curriculum. Teaching materials help both teachers and students by guiding activities and learning competencies. There is a three stage process for managing learning resources that involves identifying needs, classifying availability, and considering modifications. Developing customized teaching materials has the benefits of aligning with student needs and the curriculum, providing alternatives to textbooks, and allowing for varied and rich materials to improve communication between students and teachers. Schools need to develop their own materials to meet curriculum demands, student characteristics, and problem solving skills. Examples of material development in Finland and Indonesia are provided.