🔢 Part 1: Understanding Prime Numbers

1. What is a prime number? Write your definition in your own words:

2. Circle the correct answer: A prime number has exactly how many factors?

1 factor

2 factors

3 factors

More than 3 factors

3. Fill in the blanks:

The smallest prime number is ______. The only even prime number is ______.

A composite number has _______ than two factors.

🎯 Part 2: Prime or Composite?

4. Look at each number below. Tick the box if it is a PRIME number:

7

12

17

21

23

25

29

30

5. Choose one composite number from question 4 and list ALL its factors:

Number chosen: _______

All factors: ________________________________

6. Circle the correct answer: Which number is NOT prime?

31

37

39

41

🌳 Part 3: Factor Trees

7. Complete the factor tree for 24:

8. Complete the factor tree for 36:

9. Write the prime factorisation using multiplication:

24 = _____ × _____ × _____ × _____

36 = _____ × _____ × _____ × _____

10. Create your own factor tree for the number 45:

🧠 Part 4: Problem Solving

11. Match each number with its correct description:

1. Number 1

2. Number 2

3. Number 4

4. Number 13

A. The only even prime number

B. Neither prime nor composite

C. A prime number greater than 10

D. The smallest composite number

12. Sarah says "All odd numbers are prime numbers." Is she correct? Explain your answer with examples:

13. Find all the prime numbers between 50 and 60. Show your working:

14. Challenge: Using the Sieve of Eratosthenes method, cross out all composite numbers from 2 to 30 in the grid below. Circle the prime numbers that remain.

2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30

✨ Part 5: Reflection

15. What strategy do you find most helpful for determining if a number is prime? Explain why:

16. Rate your understanding of prime numbers today:

I need more help

I understand the basics

I feel confident

I can teach someone else

Prime Numbers Exploration

Prime Numbers Exploration

🔢 Part 1: Understanding Prime Numbers

🎯 Part 2: Prime or Composite?

🌳 Part 3: Factor Trees

🧠 Part 4: Problem Solving

✨ Part 5: Reflection

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