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✦ Class 8 · Maths
Cube Numbers
You'll see how stacking simple blocks can reveal a hidden pattern in numbers.
What this lesson covers
Step by step, in this order.
- 1Begin with a familiar object: a single sugar cube. Ask the student to describe its shape and dimensions.
- 2Introduce the term 'unit cube' and explain 'volume' as the space it takes up. Ask for the volume of one sugar cube.
- 3Ask the student to imagine building a bigger cube using these sugar cubes. Start with a 2x2x2 arrangement. Ask how many small cubes are needed.
- 4Define 'cube number' as the result of multiplying a number by itself three times. Connect 2x2x2 to 2 cubed (2³).
- 5Show a visual of a Rubik's cube (3x3x3). Ask how many smaller cubes make up the whole Rubik's cube. Relate this to 3³.
- 6Introduce the notation 'n³' as 'n raised to the power of 3' or 'n cubed'. Explain it's a shorthand.
- 7Explore properties: calculate cubes of a few small odd and even numbers. Ask if they notice a pattern in the results.
- 8Share a historical note: Ancient Indian architects used cubic blocks for building structures like stepwells. Explain how they calculated the number of blocks needed.
- 9Define 'perfect cube' as a natural number that is the cube of another natural number. Give examples like 8 and 27.
- 10Explain how to check if a number is a perfect cube using 'prime factorization'. Show how to group prime factors in threes.
How it looks
A real board, not a video.
This board is from a different Maths lesson — yours will look like this. She writes and draws while she explains, and stops to check you followed.
Doubts this lesson clears up
- What's the main difference between a square number and a cube number?
- Can a negative number be a cube number? What would that mean?
- How do we find the cube root of a number?
- Are there any interesting patterns in the last digits of cube numbers?
- Why is it called a 'cube' number, and not something else?
- Are there any numbers that are both a perfect square and a perfect cube?
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