This is a bit 'sideways' of the topic, but the discussion of factors and multiples reminded me of our work with prime numbers. My grade level colleagues liked these pages I compiled so I thought it might be helpful to others of you teaching these terms.

My students and I went through the process of figuring out which were prime numbers, discussing factors and multiples, using "The Sieve of Eratosthenes." We used a 100's grid and crossed off the multiples of the numbers as explained on this page:

**Sieve of Eratosthenes- to find the prime numbers up to 100**
http://mathforum.org/dr.math/faq/faq.prime.num.html
Along with discovering

**prime numbers**, we learned of

**composite numbers**. At the same time, we explored a bit with

**square** **numbers**. Students realized that 'square numbers' form squares when made with centimeter cubes. (2x2, 3x3, 4x4, etc)

In order to help keep all the information straight, I compiled their information and made these pages (attached)

**Page 1**-A page with the following information:

**Prime Numbers**

**A number with only ‘1’ and itself as a factor**

**2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, **

**53, 59, 61, 67, 71, 73, 79, 83, 89, 97**

**Square Numbers**

**The product of a number and itself**

**1, 4, 9, 16, 25, 36, 49, 64, 81, 100**

**Composite Numbers**

**A number with more than 2 factors; **

**not a prime number**

**4, 6, 8, 9 10, 11, 12, 14, 15, 16, 18, etc. to 100**

**Page 2**- 2 per page of a smaller 100 grid with the composite numbers grayed out and prime numbers left in white, with the above info in smaller size.

The larger page I enlarged for the bulletin board. The half page was distributed to each student which they each glued into their math vocabulary notebooks.