This study developed and validated Technology-Enhanced Lessons in Optics (TELO), particularly in teaching electromagnetic spectrum and light. It adopted the Research and Development (R&D) methodology, anchored on the Input-Process-Output (IPO) and Substitution, Augmentation, Modification and Redefinition (SAMR) models. A needs–assessment survey on selected topics in the electromagnetic spectrum and light that need technology enhancement was done first before the material was developed. A panel of evaluators who were chosen purposively evaluated the content validity of the TELO in terms of its objectives, content, activities, and assessment techniques using a content validation rating scale. The weighted mean was used to describe the content validity of the TELO. Results of the needs-assessment survey revealed that all topics in the electromagnetic spectrum and light are included in the development of the material. Results of the validation revealed that the TELO is highly valid in terms of objectives, content, activities, and assessment techniques. The TELO applies the principles that activities can be considered interesting and engaging if they are anchored on the theory of constructivism and the SAMR model as a support theory and stimulates many senses and allows learners opportunities to construct their own ideas by integrating existing knowledge with new one.