Students learn about finding prime numbers using factor pairs and the Sieve of Eratosthenes. Throughout the lesson students are recall and apply the first 12 primes to solve a range of problems.

To begin the lesson students recap finding the highest common factor of a group of numbers. In the main part they are taught to find the first 12 prime numbers using factors. The end of lesson challenges students to explore the sum of various primes.

**Differentiated Learning Objectives**

- All students should be able to calculate the first 12 prime numbers.
- Most students should be able to use the Sieve of Eratosthenes to calculate the first 15 prime numbers.
- Some students should be able to investigate any pattern within prime numbers.