🔢 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

About This Worksheet

Free in Kuraplan

Print-Ready

AI-Generated

For Teachers & Parents

Need a custom version of this worksheet?

More Maths Worksheets

Proportional Reasoning Practice

Find the Whole Proportionally

Core Scale Factors

Advanced Scale factors

Basic Scale Factors Worksheet

Proportion and Ratios Worksheet

Proportional Reasoning Practice

Proportional Reasoning Practice

Explore more free resources