## Thursday, February 17, 2011

### Head Strings: Measuring with String & Tile

We continued our lessons on measurement. The boys enjoyed Inch by Inch, in which an inchworm measures a variety of birds (a flamingo's neck, a toucan's beak, a heron's leg...) only to be told by a nightingale, "Measure my song or I'll eat you for breakfast." The inchworm "measures," moving farther and farther away as the bird sings, eventually inching out of sight.

We then continued a little measurement of our own...

Following the free Math Learning Center lesson**, "Head Strings," I measured the circumference of my head with a piece of yard, lay it on the floor, put 5 colored tiles next to it,  and asked my son to estimate how many tiles would be needed for the total length. He guessed 25 by looking at the first group of tile and explaining it would probably take 5 of those to finish the string. I put tile along about half the string and asked if he wanted to revise his estimate. With 11 tile now along the string, he changed his estimate to 22. He measured the string with tile, finding that it took 23.

I removed the tile and placed a book next to the string, asking him to use what he knew about the string to estimate the length of the book. He estimated and measured, coming within one tile. I gave him a copy of "Head String Record Sheet," (free pdf) and let him estimate and measure various objects around the house using his own head string and tile. Lastly, we'll be considering how many tile are needed to measure the length of a ruler and reflect on what that says about the size of each tile. (Tile are 1" square.)

My 4yo measured for a bit and then made a train and house with his felt shapes.

**To access the free lesson, including blackline pdfs, go here and download "D2 Measurement: Length in U.S. Customary Units."