Here is the link to the SCED 2.0 Subject Codes drafted by the NCES Forum that were rolled into CEDS v4:
https://ceds.ed.gov/CEDSElementDetails.aspx?TermxTopicId=22747Note: The first 2 digits of a 5 digit SCED code match these codes for subject. CEDS also includes things like CIP codes used more in post secondary but recommends SCED for U.S. K-12. Having a separate field for Subject Code and Subject Code System allows for some flexibility and potential crosswalk rather than a free for all and data quality issues, e.g. Mathematics, Math, Msth, math, Maths, Geometry, Number Sense, ...though if like-organizations can agree to a conventional system, even better.