Lesson 3: Arrays and Equal Groups

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.

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:

He should write the following:

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):

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).

Your child will complete Basic Skills Reviews during each unit over the course of this year. The number of the reviews will vary based on the length of the unit. The purpose of these reviews is to keep fundamental math skills that your child should have already mastered — such as addition and subtraction, telling time, and counting money —"fresh" in his mind so that he doesn't "lose" them over time. As your child learns new skills this year, these skills will also be incorporated into the reviews. If needed, allow him to use manipulatives, but encourage him to try to find the answers without them first. If he struggles with specific items on the reviews, you may want to look back to previous units and lessons and provide time for him to revisit activities or replay games. He can also refer to his Interactive Notebook for review of previous material, but encourage him to complete the review sheets from memory and by using what he knows as he's able. Most review sheets have at least one money-related question; you may want to have quarters, dimes, nickels, and pennies available for your child to use as he works.

Your child will complete the "Basic Skills Review #1" sheet. Give him a scratch sheet of paper to use as needed. For a review of time and money, your child can refer to the "Time Review" and "Money Review" sheets. These sheets can be stored in his Interactive Notebook for future reference as needed.