February 03, 2005

Intro to Measurement

Typically I prepare for science class at the last minute and I've been really lucky. All my science experiments have worked out when tried the night before. I may have gotten too ambitious in creating my own ferrofluid (I made ferromud) or building my own thermometer (too easy to make the play-dough appear to change the temperature).

At the last minute, I decide to go back to basics. How could I think about teaching measurement of temperature before teaching measurement of length?

I did a little research into early measurement with feet and inches and I put together a worksheet of measurement activities and found a nice printable ruler.

I started with the class sitting on the rug. I asked them how I might figure out whether the rug would fit into my living room without carrying there and trying it out. One kid suggested that I could measure the rug using the pointer -- there's a classroom pointer with a little wooden dinosaur on the end. I proceeded to measure the rug and discover that it was three pointers and two dinosaurs long.

Now, suppose I couldn't take the pointer with me. How would I measure the rug? One of the kids gave a perfect intro to my history of measurement talk by saying I could use my thumb. We talked about etymology and I think they really enjoyed hearing about Spanish, French and Italian, but an explanation of the Latin orgins of the English word went a bit over their heads. Then I asked for an easier way to measure something big (the rug, after all, would be an awful lot of thumbs), and they easily came up with feet. After a brief discussion of the metric system, we proceeded to the activities.

I think most of the kids had fun, and measurement is a key concept for scientific activities. However, later that day, my son said that it was even more boring than putting rocks in water. (For the record, there were some kids who wanted to repeat the section where they put rocks in water.)

Historical notes

Inch: At first an inch was the width of a man's thumb. In the 14th century, King Edward II of England ruled that 1 inch equal 3 grains of barley placed end to end lengthwise. -- Origins of Measurement

"The word for "inch" is similar to the word for "thumb" in some languages. French: pouce inch, pouce thumb; Italian: pollice inch, pollice thumb; Spanish: pulgada inch, pulgar thumb; Swedish: tum inch, tumme thumb." -- wikipedia

In English, the word comes from a differnt root: "'linear measure, one-twelfth of a foot', late O.E. ynce, M.E. unche (current spelling c.1300), from L. uncia 'a twelfth part,' from root of unus "one;" an early borrowing from L., not found in any other Gmc. language." -- online etymology dictionary

Yard: At one time, a yard was the length of a man's belt or girdle, as it was called. In the 12th century, King Henry I of England fixed the yard as the distance from his nose to the thumb of his out-stretched arm. -- Origins of Measurement

The english word for yard comes from Old English and Saxon words for "rod" or "stick." "In O.E. it was originally a land measure of roughly 5 meters (a length later called rod, pole or perch). Modern measure of "three feet" is 14c." -- online etymology dictionary

More from the Origins of Measurement:

Hand: A hand was approximately 5 inches or 5 digits (fingers) across. Today, a hand is 4 inches and is used to measure horses (from the ground to the horse's withers, or shoulder).

Foot: In ancient times, the foot was 111/42 inches. Today it is 12 inches, the length of the average man's foot.

Pace: The ancient Roman soldiers marched in paces, which were the length of a double step, about 5 feet; 1,000 paces was a mile. Today, a pace is the length of one step, 21/2 to 3 feet.

Posted by Sarah at February 3, 2005 09:00 PM