In October 2023 the first official version of the General Metadata Profile for Educational Resources (AMB – Allgemeines Metadatenprofil für Bildungsressourcen) was published, a schema.org-based specification on how to describe educational resources with structured data in JSON-LD. Though the metadata profile was developed by and for German-speaking OER initiatives, it may well be worth adapting in other contexts. The spec was the result of a 3.5-year-long process involving individuals and organizations from the library field, from education and private initiatives. The GitHub repo alone shows 17 contributors, others have contributed by opening issues or adding to the discussion in meetings. During the development, issues where opened at schema.org and contributions where made to controlled vocabularies of LRMI (Learning Resources Metadata Innovation) published within the Dublin Core Metadatadata Initiative (DCMI). The AMB had already been adopted and implemented by different players when in draft status and is pushed by different players especially in the educational sector. It has been a notable tool for bringing good metadata practices on the Web, like SKOS, into projects from the education sector. The talk will briefly introduce purpose and scope of the metadata profile, describe the tools and processes used for the development, examine motivations for joining the development community and the benefits of implementation. It will close with challenges and lessons learned e.g. regarding tools, community work, and contributions to upstream standard specs.