[nickpeterson]

https://www.amazon.com/My-Little-Big-Math-Book/dp/9198282603

I have not read this, but it's from the same person who helped create "anchor modeling" and I find that quite interesting.

[gowld]

From the "Look Inside", it strangely pairs very "childish" pictures with small-font densely-packed pages high-school or college-level mathematical prose.