The website mentions some good courses, personally I love Richard Borcherds' YouTube channel[1] for both undergraduate and graduate courses. No frills, exceptio

The website mentions some good courses, personally I love Richard Borcherds' YouTube channel[1] for both undergraduate and graduate courses. No frills, exceptionally clear, (mostly) bite-sized lectures that cover a good range of material (especially in geometry). Something that might interest HN's demographic is Kevin Buzzard's Xena Project[2], centered around proof systems (in Lean). The natural numbers game [3] is particularly fun IMHO. I don't know if it counts as learning materials per se but it's certainly instructive. [1] https://www.youtube.com/channel/UCIyDqfi_cbkp-RU20aBF-MQ/playlists https://www.youtube.com/channel/UCIyDqfi_cbkp-RU20aBF-MQ/pla... [2] https://xenaproject.wordpress.com/ https://xenaproject.wordpress.com/ [3] https://www.ma.imperial.ac.uk/~buzzard/xena/natural_number_game/ https://www.ma.imperial.ac.uk/~buzzard/xena/natural_number_g...