Do you know why a pound is abbreviated lb? Or how long is a fathom? Or a furlong? Where do their names come from? What about how many acres does a section cover? How about how heavy is a dram? Or how long does an eon last?
Our eleven year old loved this interesting and clever new picture book, and so did I. It is illustrated with very nice photographs.
Also, it does talk about that international system Americans have become allergic to, and purposely ignore, and yet will eventually have to come terms with: the Metric System. But only briefly, since an explanation of the metric is, to the customary system, as the distance from the earth to the moon is when compared to the distance from the earth to the sun.
Just had to say that. The Brazilian (and metric) side of me.