Course library / Unit cubes and volume
Upper primary · Geometry & space
Volume is more than a formula. Count one layer, then count the layers.
Preparing the 3D model…
Predict: how many cubes are in a 4 × 3 layer? How many are in two layers?
Each row on the base has “length” cubes and there are “width” rows, so one layer has length × width unit cubes. Stack “height” identical layers and the total is length × width × height. Each unit cube has a volume of 1 cubic unit, so the cube count is also the volume.
Example: length 4, width 3, height 2. Each layer has 4 × 3 = 12 cubes. Two layers have 12 × 2 = 24 cubes, so the volume is 24 cubic units.
Area and volume use different units. The base is measured in square units; after multiplying by height, volume is measured in cubic units.
Three questions for independent practice, with a separate answer page.
Name: __________________ Date: __________________
1. What is the volume of a prism with length 5, width 2 and height 3?
2. Each layer has 12 unit cubes. There are 4 layers. How many cubes are there?
3. Draw a rectangular prism with a volume of 12 cubic units and label its length, width and height.
