Over the last month and a half I've been working on a book on MIPS assembly programming targeted primarily at college students. I did this for two reasons. First because MIPS is one of the most in-demand subjects in my tutoring (followed by RISC-V which is growing). Secondly, because it was an excuse to learn asciidoctor, a more powerful alternative to markdown.
The latest version will always be available here.
It also comes in pdf form.
Lastly, you can see the repo (which includes some example code that is referenced in the book) here