Ana, last year, had to do a few homeworks on measurements.

[conuly]

No doubt she'll have to do so again this year, because instead of teaching anything straight out in math, in the US we tend to "spiral" and teach ever advancing versions of the same concepts year after year. I've read that this is an inefficient method of teaching math, but I only read it once.

The stated goal of Ana's homework on measurements last year was, repeatedly, basically to learn that standard measurements are "better" than measuring through nonstandard units like thumb-widths or human feet... which of course were in many ways the origins of our standard units today, unless you use metric. This annoyed me at the time, because it made no acknowledgment of the fact that, actually, nonstandard units are, in some ways, superior to standard ones. We're so used to our standardized world that we don't think that way, but I can think of one easy advantage to measuring by hand and thumb instead of by inches - if you're counting out five thumbs of space on your fabric, or two handfuls of pepper in your peppergrinder, or three paces to bury the body, you NEVER have to resort to tools to figure out if you have the right amount. Instead, all the tools you need are right here on your own body. There are definitely disadvantages to this system, sure, but that doesn't mean that the standardized systems are the best. They each have their pluses and minuses, whatever the homework might state.

Which leads me to Wikipedia, and to shoe sizes. Listen!

barleycorn
Basic Anglo-Saxon unit, the length of a corn of barley. The unit survived after 1066, as the base unit from which the inch was nominally defined. 3 barleycorns comprising 1 inch was the legal definition of the inch in many mediæval laws, both of England and Wales, from the 10th century Laws of Hywel Dda to the 1324 definition of the inch enacted by Edward II. Note the relation to the grain unit of weight. This archaic measure is still the basis for current UK and U.S. shoe sizes, with the largest shoe size taken as thirteen inches (a size 13) and then counting backwards in barleycorn units,[4] although the original derivation was: less than 13 barleycorns: infants with no shoes; 13 to 26 barleycorns: children's sizes 1 to 12; 26 to 39 barleycorns: men's sizes 1 to 13.

Yes, you heard it here first. WHY are shoe sizes so weird? Because, unlike anything else on this good green earth, they're based upon a unit that's a third of an inch. Sheesh.

(And listen, while we're on the subject. For all the easy math of the metric system, I've always had a real fondness for our system and all its halves and doubles.)

Comments

[beezelbubbles.livejournal.com]

In my days working as an electrician in my university's theatre, we used our bodies to measure all the time. Elbow to fingertip is pretty reliably near to 18 inches, handspan is generally 6... Mush easier than futzing with a tape measure at the top of a 65 foot cherry picker while you're trying to hang a light fixture. =D Of course, most of us took a tape measure to ourselves so we'd know for sure how much we were "off". (This did not work for the carpenters or welders, as they had to be far more precise than we did. Light is more forgiving of being off a couple of inches than wood or metal.)

[oloriel.livejournal.com]

*snickers*

The barleycorn and the inch and the mile and all that are lovely, but I can't help feeling grateful to Napoleon for forcing the metric system upon my home country. ;) If you standardise (and nothing stops you to use your own body for measurements, regardless of whether or not there is a standardised system...), you may as well do it in a way that's easy for calculation. Even the Brits gave up their weird monetary system eventually...

That said, we had to make a list of our body measurements for math class one day, and actually convert everything into thumbs and spans and ells and whatnot. I suppose the value of that lesson was that we learned how to use our body for measurement, should we ever need it, and were introduced to a different system of measurement... but it was still rather weird. (More weirdly, we did that years before we practiced converting kilometers into miles, or Celsius into Fahrenheit...)

[marveen.livejournal.com]

I've read that this is an inefficient method of teaching math, but I only read it once.

Well, you're hearing it from me again. :) I can't remember who I read it in, but I remember reading the same criticism aimed at the school curriculum in general. Specifically, he graphed the materials covered each year as a bell curve, and said he would prefer that each year overlap and re-cover the previous year's materials by perhaps ten percent. Instead, the graph he created to represent actual practice in the schools overlapped like sixty percent. His desired ten-percent overlap occurred not with the year just finished, but with two years back. O.o

That sounds exactly like what my school did, which is why as a child I got so screamingly bored with it that I ended up refusing to do the work. (So I didn't exactly have a firm grasp of cause and effect over the long term--I was eight, okay?)

For a recent discussion on our schools and homeschooling, see this entry in mock_the_stupid (http://community.livejournal.com/mock_the_stupid/3223038.html).

The easy and compromise solution is to measure with tools how wide your thumb is and how much flour you can grab in a handful and remember those numbers. That way you don't need to dig out the tools. ;)

Also, isn't a centimeter somewhere within shouting distance of a third of an inch? (What's a centimeter derived from, anyway? A barleycorn, only instead of multiplying by 3/36/etc., it's multiplied by 100/100,000/etc.?)

[conuly]

SIXTY PERCENT OVERLAP? Sheesh.

[conuly]

Well, that thread was fun. For somebody who wasn't interested in talking about "all homeschoolers", she certainly seemed to be doing just that!

[marveen.livejournal.com]

Yeah, funny how lots of people get all tetchy about "Don't generalize!" when it comes to their own sacred cows, but they're often ready and willing to generalize about other people's.

I don't have any children or the care of any, but I'll put my general knowledge (to about sophomore level in high school) up against the average teacher's any day.

[oloriel.livejournal.com]

A centimeter is derived from a meter, which in turn supposedly the ten millionth part of the earth meridian quadrant (direct distance from the North Pole to the equator or some such), which is what they chose as the new, no-nonsense, unmythological measurement during the Reign of Terror. I suspect that the similarity to the barleycorn is purely coincidental.