Math6-8
Prime Number Patterns: Sieve of Eratosthenes Practice
By Allison A.
A practice set for 6th graders that walks students through the Sieve of Eratosthenes to find primes up to 100, building understanding of prime and composite numbers along with long division skills. It's a hands-on enrichment packet suited to a single math block or small-group work.
Customize for your classroom
Teacher Guide & Tips
- Use as a 30-45 minute enrichment activity after students have a basic grasp of factors and multiples, working individually or in pairs on the 10x10 grid.
- Discussion question: Why do we only need to check multiples of primes up to 10 to find all primes up to 100, and what would change if the grid went to 200?
- Scaffold for struggling readers: Provide a pre-marked grid showing the first few steps (crossing out 1, circling 2 and its multiples) so students can see the pattern before doing it independently.
- Extension for advanced students: Ask them to explore twin primes or find the largest prime gap within the grid, and to pair the sieve with long division checks on composite numbers.
- Estimated time: about 35 minutes for the sieve, plus 10 minutes for the long division extension.
Math6-8
Prime Number Patterns: Sieve of Eratosthenes Practice
By Allison A.
A practice set for 6th graders that walks students through the Sieve of Eratosthenes to find primes up to 100, building understanding of prime and composite numbers along with long division skills. It's a hands-on enrichment packet suited to a single math block or small-group work.
Customize for your classroom
Teacher Guide & Tips
- Use as a 30-45 minute enrichment activity after students have a basic grasp of factors and multiples, working individually or in pairs on the 10x10 grid.
- Discussion question: Why do we only need to check multiples of primes up to 10 to find all primes up to 100, and what would change if the grid went to 200?
- Scaffold for struggling readers: Provide a pre-marked grid showing the first few steps (crossing out 1, circling 2 and its multiples) so students can see the pattern before doing it independently.
- Extension for advanced students: Ask them to explore twin primes or find the largest prime gap within the grid, and to pair the sieve with long division checks on composite numbers.
- Estimated time: about 35 minutes for the sieve, plus 10 minutes for the long division extension.