Use this fun activity with your multiplication unit! This helped my second graders to understand arrays, repeated addition, and the communicative property of multiplication. It's a hands-on, tasty, and visual way to get those brain juices flowing. I used Cheerios for this activity- anything larger would limit your mulitplication fact choices. ;)
Here's an example: Tell your class to build the number sentence 3 x 5. The students would take 5 Cheerios and put them in a row at the top of the first box. Then they would take 5 more and line them up right under the cereal a the top, then repeat this one more time. The addition sentence would be: 5+5+5=15. The box at the bottom would contain 5 rows of 3, and the repeated addition sentence would be: 3+3+3+3+3=15.
You could do this with square numbers for enrichment and have them lay out 4 x 4=16. They would then be able to clearly see why these are called square numbers.