When thinking of elementary lessons that fascinated us with a sense of reason, this writer is reminded of the spinning top. Her mother pulled it out from a basket of old toys to put up a mini show of earth’s rotation. A few years later, the instance of the spinning top was used in school to explain the conservation of angular momentum against small torques — like the effect of gravity on the twirler. Practical activities somehow yank concepts out of fat textbooks to place them before our sparkling eyes. Thereon, the possibilities seem endless.

A scene from The Recycling Lie