Use tiles to explore Prime and Composite!

Hey there! I can't believe it's already Thanksgiving. Happy Thanksgiving to all of you.

Wow, this week is just packed with new learning before the kids are off! We are studying prime and composite numbers in group. Today, we did a great investigation using tiles. For this activity, you'll need a multiplication table and tiles. I also used my Prime and Composite Task Cards

Before we started, we talked about what an array is and how building arrays can help us identify prime and composite numbers. We can see the number of rows times the number of columns and the number of columns times the number of rows. 


An example of an array is below.

column x row 
6 x 3
row x column
                                           3 x 6

Here's our prime and composite question. 

I passed out 16 tiles to each student and let them build different arrays. After a student discovered an array, we wrote the factors together on a sticky note.

So, we discovered that the number 16 is composite because it is composed of more than two factors: 1, 16, 2, 8, and 4. The kids had fun manipulating the tiles! As a follow up to the tiles, we identified the factors of 16 on the multiplication table: 2 x 8 = 16 and 4 x 4 = 16. 

Then, we investigated the number 7. Is 7 prime or composite? 

Here's our work. 

We discovered that 7 is prime. Check out the incomplete arrays the students built. We talked about examining if a number is divisible by 2 or divisible by 3. We grabbed 2 tiles at a time and it didn't make a complete array. Then, we grabbed 3 tiles at a time and it didn't make a complete array.

Hope this can add to your math discussion. Have fun identifying more prime and composite numbers!