Learning About Prime and Composite Numbers

In this lesson, students will learn about prime and composite numbers.

First, you will copy the worksheet I have included in this lesson so that each student will have a copy.

Then, you will explain about prime numbers and composite numbers.

A prime number has only two factors. It has the number itself and number one. 47 = 1, 47

A composite number has more than two factors.

For example: 4 has 1, 2, 4 as the factors: 1 x 4 = 4 and 2 x 2 = 4.



After that, you will pass out the worksheets so that the students can work on them independently. Worksheet - Prime and Composite Numbers

Directions: Write Prime or Composite after each number.

1. 17

2. 24

3. 35

4. 19

5. 2

6. 7

7. 18

8. 29

9. 31

10. 42

11. 46

12. 50

13. 9

14. 16

15. 44

16. 47

17. 33

18. 75

19. 85

20. 27

Answer Sheet

1. 17 = Prime

2. 24 = Composite

3. 35 = Composite

4. 19 = Prime

5. 2 = Prime

6. 7 = Prime

7. 18 = Composite

8. 29 = Prime

9. 31 = Prime

10. 42 = Composite

11. 46 = Composite

12. 50 = Composite

13. 9 = Composite

14. 16 = Composite

15. 44 = Composite

16. 47 = Prime

17. 33 = Prime

18. 75 = Composite

19. 85 = Composite

20. 23 = Prime

Each question is worth five points.

100 to 90 = A

89 to 80 = B

79 to 70 = C

69 to 60 = D

Below 60 = F