During the first week of school, after we've decorated our math journals, we practice our multiplication table. We usually do our multiplication table during the first few minutes of class after our math warm up. Then we begin our Factor Ts. We use these throughout the year. I teach prime/composite, divisibility rules, odd/even, factors, multiples, GCF, square numbers, reducing fractions, and so much more. It's really important that the kids have the correct answers because we use them all the time. It follows the same idea of factoring that most people call the rainbow method, which drove me insane since being a tad OCD, I never put enough space for numbers with many multiples (like 24) and put way too much space for those pesky prime number that were large (like 61). Usually the second day of class, I allow the students to pick one partner. Yes, I allow them to pick a friend if they choose, but after this time, they usually pick someone other than their friend. There's something about learning for yourself that your best friend is not always the best partner during academic assignments. lol
1. Partner up
2. Calculator - I allow them since the focus of this is not to see if they can multiply but to determine all the factors.
3. Assign them a set of 10 numbers (we do 1-100)
4. Give them some time (about 30 minutes) to come up with their factors. During this time, many of them will begin to use strategies like skip counting. I usually circulate the room and discuss divisibility rules.
5. Depending on time
6. Afterward, we discuss divisibility rules again and show lots of examples. We color code our prime numbers and square numbers. These factor Ts are a great way for students to get a visual of prime numbers and square numbers.
Here's some pics
Below - you'll see color-coding the prime and square numbers - this will open up the conversation of the number 1. Kids will question why it's not prime. Read the definition to them and have them point to the factors - it will help them understand why it's not prime or composite. BTW....49 always throws them - they will forget 7x7 - be ready
If you want a copy of the Factor Ts, leave me your email address in a comment and I'll send it. Or you can click on the last picture, and it'll take you to TpT to download it for free.