Lovely, as all neal.fun experiments. <3
My favorite is probably https://neal.fun/infinite-craft/
This type of interactive learning experience reminds me of how fun it was to browse Encarta back in the day. It was full of interesting facts, presented in fun interactive ways. As much as I love that we have Wikipedia today, a static web page with text and limited multimedia is far less engaging and conducive to learning.
I think that Neal Agarwal and Bartosz Ciechanowski should be sponsored by the Wikimedia Foundation to create similar experiences on Wikipedia. That would do so much to facilitate learning for students of all ages.