Math lesson plan · 4th grade (Year 5 in England) · 45 minutes
Cube numbers and the ³ sign
Number sense
CCSS 6.EE.A.1England: Y5 Multiplication and division
Objective and success criteria
Students will: Cube numbers and the ³ sign.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Square numbers and the ² sign
Leads to: Calculate with squares and cubes; Volume by counting layers of unit cubes
Materials: Place value chart, Base-ten blocks or a number line, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Square numbers and the ² sign). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Which of these is a square number? (24 / 27 / 25 / 26) → 25Prompt: A square number is a number times itself.
- Ines says 8² = 16. Spot the mistake. What is 8²? → 64Prompt: 16 is 8 × 2. Is that what the ² means?
- Ravi says 5² = 10. Spot the mistake. What is 5²? → 25Prompt: 10 is 5 × 2. Is that what the ² means?
Hook · 5 min
- Show a number in the news or a price tag and ask what each digit is worth.
- Share the objective: Cube numbers and the ³ sign. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: What is 2³?
- Step 1: 2 × 2 = 4
- Step 2: 4 × 2 = 8
- Answer: 8
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- What is 5³? → 125Prompt: 5³ means 5 × 5 × 5.
- Which of these is a cube number? (125 / 126 / 123 / 75) → 125Prompt: Cube numbers: 1, 8, 27, …
You do: independent practice · 10 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- What is 3³? → 27Prompt: 3³ means 3 × 3 × 3.
- Which of these is a cube number? (9 / 6 / 16 / 8) → 8Prompt: Cube numbers: 1, 8, 27, …
Watch out for
- Reading 1,045 as one thousand four hundred five: point to each place and say its value.
- Thinking a longer number is always bigger, even with decimals (0.45 vs 0.5).
Support and stretch
Support
- Review first: Square numbers and the ² sign.
- Use concrete materials: place value chart.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Move on to: Calculate with squares and cubes; Volume by counting layers of unit cubes.
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/math/grade-4.
Free lesson plan from eurekami.com/lesson-plan-builder