What's in a pencil?

This week my students and I were having our usual rap session about this, that and the other. I'm not sure how this came up, but at one point I told them about what has to be one of my all time favourite videos: I Pencil, based on a 1958 essay by Leonard Read

I will post that video here and then a series of videos with many of the ideas that underpin the I Pencil video.

It's hard to think of anything more low-tech than a pencil. After you've watched the video, I hope it will be hard to think of anything more fascinating!