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Janet Elkins Douglass Middle Math & Science Academy
543 N. Waller
Chicago IL 60644
Middle grades through 8th
1. Practice with linear metric measurement
2. Appreciation of differences/acceptance of diversity
2-meter stick several 1-meter sticks flexible metric tape lines
paper/pencil calculator 3 X 5 cards
1. Have students guess if they are rectangles or squares if one compared the
individual's height with the measurement of fingertip to fingertip of the
outstretched arms. Mount a 2-meter stick along a free area for taller
students. Group will take each others measurements, and determine if
the guesses were correct. Take hand count of those who were surprised by the
2. Task is to determine the PERCENT or PROPORTION that the legs are of the
total height per student. The "nice" way to take this measurement is to have
the person being measured hold a 1-meter stick horizontally AT the top of the
legs. Partner will then measure from the floor with another meter stick.
Height is already known. Percent is found by dividing the leg length BY the
height, then TIMES 100. EXAMPLE: legs 84 cm divided by height of 200 cm = 42%
Write the percent legs you are on your 3 X 5 card. Students will arrange
themselves in an increasing or decreasing line by the legs proportion.
OBSERVE the differing heights all along the line. Reassemble with height being
the determining factor. Observe differing leg proportion with students on
each side of you.
1. Teacher observation
2. Student "a-ha" at diversity of leg proportion vs. height accompanied by
verbalization or written group report.
3. Students repeat activity with the HEAD height being the proportional factor.
There are some proportions that are different during our lifetimes. Ask
students if a baby's legs would be the same proportion as ours. (No) Ask when
leg growth spurt PROBABLY starts. (Teens) * The diameter of the fist is
approximately the length of a foot. (Useful to know when you are buying socks
and don't want to take off your shoes!) * Twice to three times the
circumference is approximately your height. * The measurement between your
wrist and your elbow is also approximately your foot length. (Fool others by
asking for the wrist to elbow length, then say that you can "guess" who has
the biggest or smallest feet.