Grade Level: 4-5 Time Duration: 1 class periods Vocabulary: ratio, proportion, scale Grouping : pairs Materials Per Group: pre-measured reference stick at least one foot long measuring tape paper and pencil a field or large open space Procedure: measure the reference stick to the nearest inch place stick vertically in the ground measure the shadow of the stick with measuring tape measure the shadow of a tree (if there is no tree, have students measure each other's shadow) calculate the tree (or student) height (solve for x ) with a ratio by cross multiplying See the figure below: American Indians in the northwest had a related method of measuring the height of an object.
(a ratio by cross; multiplying; )
a ratio by cross
multiplying