standard_description: Apply the area and perimeter formulas for rectangles in real world and mathematical problems. For example, find the width of a rectangular room given the area of the flooring and the length, by viewing the area formula as a multiplication equation with an unknown factor.
problem_activity: Task
Materials:
Sheets of paper for each student that are folded in half with the words "Heavier" and "Lighter" written at the top of each side.
[IMG]
A box of large blocks.
A box of different objects with different weights to compare with a block from the first box. Some should be lighter than a single block and some should be heavier. The weight differences should be fairly pronounced.
Action:
The students begin by choosing a block that they will use to compare with other objects.
Students will then choose an item from the second box and compare its weight to their block. They then draw a picture of it under "Heavier" or "Lighter" depending which applies. They continue to choose objects from the box to measure against their block until they have two or three drawings on each side of their sheet.


aligns: no