Have been out of the Sciforums loop since Easter. In that time all 3 STEM Development papers have been updated with adjustments made to many figures. Several reported discrepancies have been fixed - probably still quite a few lurking. Exchemist might be pleased with the modified use of the term 'energy' and the introduction of the concept of 'energen'. The 3 papers cover the topics of atomic structure; the nature of light and other forms of EMR; and electrons, electricity and magnetism. They are all linked and cross-referenced, so you can start with any one of the 3. All the latest releases are timestamped May 2022. The links are the same as before- just the content has changed. Those links by topic are: Atomic Structure; Electrons and Electricity; The Nature of Light. Please have (another) look.