Grade 5 · Math · Lesson 22

Volume Intro (Unit Cubes)

Volume is the amount of space inside a 3-D solid. We measure volume by counting how many unit cubes fit inside the figure with no gaps and no overlaps. Each unit cube has edges of 1 unit, so its volume is 1 cubic unit.

What this lesson teaches

1Define volume as the number of unit cubes that fill a solid figure
2Count unit cubes in a rectangular prism to find its volume in cubic units
3Apply the formula V = l x w x h to compute the volume of a rectangular prism
4Label volume answers with the correct cubic unit in customary (cu in, cu ft) or metric (cu cm, cu m)

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