Check out the Math & Physics Problems wiki!
https://math-physics-problems.wikia.com/wiki/Math_%26_Physics_Problems_Wikia
It's an archive of neat math, physics, and computing problems that are great for high school and university students. My goal is to spread the art and culture of mathematical problem solving.
One of my areas of interest is the scientific history of ancient civilizations, especially the scientific development of the Orient. Check out Special Pages for interesting articles and interactive timelines on the history of math and science.