old school syllabi: The Open Syllabus Project
modern internet syllabi:
- Susan Fowler's guide for learning physics
- How To Think About Cryptonetworks
- Computer Science
- Cryptoeconomics
- Microscopy Train for advanced research
- 中國哲學書電子化計劃
- Quantumcomputing
- 业余无线电通讯
There are five projects I know of doing something in this space: Learn Anything, which lets people upvote the best resources for learning any topic, Gooru, which lets teachers use existing content on the web to create courses for K-12 content, Holloway and Golden, which are creating open source guides, and Hyperreadings, which is a permanent archival library plus curated reading guides on top. I am sure there are more.