# Lesson 3: Arrays and Equal Groups

## Activities

### Activity 1: Overview of Multiplication Strategies

Materials: laminated multiplication strategies mat (kit)
Show your child the video at the following web link. Explain to him that he already knows the strategies in the video but that the video will help him see how they relate to multiplication.
Once your child is finished watching the video, ask, "What are the four strategies for multiplying?" He should recall the following: arrays, equal groups, repeated addition, and number lines. Now, show him the laminated multiplication strategies mat from the math kit, and point out each section for each strategy. Explain that, after he has practiced each strategy, your child will use this mat to represent and solve multiplication sentences in different ways.
Multiplication Strategies Mat

### Activity 2: Arrays and Multiplication

Materials: Cheerios, Goldfish, or another small snack food, fine point dry-erase markers (kit), whiteboard (kit)
Ask your child to draw an array on the whiteboard and explain its parts and what it shows. Next, he will watch the video at the following web link. Explain that he already knows much of what the video explains at the beginning but that he will also begin to see how arrays help with multiplication. While he watches the video, write the following on the whiteboard, leaving space for an additional number sentence: "___ groups of ____" and "___ × ___."
Once your child has finished watching the video, give him a cup of Cheerios, Goldfish, or another small snack, and ask him to create an array that shows the number 18 in 3 rows. He should show 3 rows with 6 items in each one. Once he has created the array, give him the whiteboard and a dry-erase marker, and tell him to write the following based on the array:
• Word form ( ___ groups of ___ )
• Number form ( ___ × ___ )
He should write the following:
• 3+3+3+3+3+3 OR 6+6+6
• 3 groups of 6 OR 6 groups of 3
• 3×6 OR 6×3
Repeat this process for the number 20, but this time don't give him a specified number of rows. He should create one of the following arrays: 2 by 10, 10 by 2, 4 by 5, or 5 by 4. Again, once he's created his array, he should write the following on the whiteboard (erase his previous numbers):
• Word form ( ___ groups of ___ )
• Number form ( ___ × ___ )
His answers will vary based on the array that he creates.

Your child will complete the "Multiplication Arrays" sheet by filling in the four blanks under each array. Explain that at this point he is only writing the word and number forms for each array and that he is not providing the products (answers).