We found a nice little example problem in Art of Problem Solving’s Introduction to Geometry book today.
They give you a picture of an equilateral triangle with three circles of equal size inscribed in it and then ask you to find the length of the side of the triangle given the radius of the circles.
When I saw the problem I thought it would make for a fun example of problem solving in geometry. My son’s walk through the problem turned out to also be a great example of what learning math sometimes looks like:
Mike's Math Page 