Sharing hinged tiling quadrilaterals with kids

Saw a really neat tweet from John Carlos Baez last week:

Finally got a chance to share this site with my younger tonight. This site is fantastic to share with kids – my son enjoyed playing around with the tiling patterns, and it was also really interesting to hear him try to describe what he was seeing.

Here’s his initial look at the site:

Here’s his reaction and play with the part of the site that allows you to create and manipulate new quadrilaterals:

This is a wonderfully easy site and a really fun idea to play with. I think with older kids it would be nice to see them try to think through why the cyclic quadrilaterals have this hinged tiling property, but I thought that might be a little much for my younger son. We’ll do a follow up exploring those ideas soon, though.