Arrays are a big theme in the new Common Core standards, starting in 2nd grade (2.OA.4 – Use addition to find the total number of objects arranged in rectangular arrays with up to 5 rows and up to 5 columns; write an equation to express the total as a sum of equal addends).
Learners need a lot of experience with arrays to understand the concept and the importance with factors, multiplies, area, and multiplication.
Here are some ideas you can use in your classroom:
- Go on an array scavenger hunt to find arrays in the classroom like shelves, window panes, bricks, grids, etc. You can also have them find objects that can be arranged into an array – like items that can be counted by 2s, 4s, 5s, etc.
- Set out objects (buttons, toys, blocks, etc) on each table. Have learners make arrays, trying to make as many arrays as possible and write matching repeated addition sentences or multiplication expressions. You can limit them to 16 objects, 24 objects, or anything that will show a variety of arrays.
- Lead a discussion on why we need to learn about arrays? Do arrays help us count quicker? How would you explain to someone else how to best count an array? Can any amount be arranged into an array?
- Demonstrate that eight counters can be put into two groups with the same number in each group (four). What other can be put into two equal groups?
Definition of an Array
An array is any arrangement of things in rows and columns. You can write an addition equation to show the representation of the model. If you have 4 rows of 5, you would write 5 + 5 + 5 + 5 = 20. Some key words include: rectangular array, addends, row, column, repeated addition, and equal groups.
Please check out my various teaching resources that focus on arrays:
Array slide show – 2-3 grade This helps you introduce arrays using real life pictures.
Arrays around us – 2-3 grade This is a set of real-life photo cards. Enter the giveaway below for a chance to win these cards!
Array task cards – 3-4 grade For your advanced learners, perfect for introducing the concept of double digit multiplication.
Array flash cards – 3-4 grade To help your learners memorize their math facts, by visualizing the arrays that match the fact.
Thanks for making math magic!
– Evil Math Wizard