Same Math › Grades 2–3 › Arrays
What is an array in math?
An array is a set of objects in equal rows and columns, like eggs in a carton. Kids use arrays to see multiplication: 3 rows of 4 is 4 + 4 + 4, which is 3 × 4.
- 3 rows, 4 in each row. Every row is the same.
- Add the rows: 4 + 4 + 4 = 12.
- Or multiply: 3 × 4 = 12. Turn it sideways and it's 4 × 3.
Why schools teach it
It shows what multiplication means
Second graders use arrays up to 5 rows and 5 columns and write the total as a sum of equal addends, like 4 + 4 + 4 = 12 (2.OA.C.4). In 3rd grade the same picture becomes 3 × 4 (3.OA.A.1).
Arrays also show why 3 × 4 and 4 × 3 match: it's the same array turned sideways. Later, splitting an array in two is the break apart strategy, and filling it in becomes the area model.
At the kitchen table
What to say, and what to skip
Say this
How many rows? How many in each row?
Can you write it as an adding sentence?
4 + 4 + 4 = 12 for 2nd grade.Now as a times sentence?
3 × 4 = 12 for 3rd grade.Where do you see arrays at home?
Egg cartons, muffin tins, windows. Kids enjoy spotting them.
Skip this
- Mixing up rows and columns.Rows go across, columns go down. Classes usually say the rows first.
- Counting every dot one by one.Count one row and add it again. That's the skill.
- Drawing rows of different lengths.Every row must be equal, or it isn't an array.
See it in action
Solving 4 × 6 with an array
Draw 4 rows of 6 dots
Add the rows
6 + 6 + 6 + 6 = 24Write the multiplication fact
4 × 6 = 24
If 4 × 6 is hard, split the array: 2 rows of 6 is 12, and two of those make 24.
Free practice sheet
Make an arrays sheet
Loading practice sheet…
Fridge cheat sheets
Math Fridge Cheat Sheets
Every K–8 math method in one printable book (159 pages): a cheat sheet page like this guide, plus a practice sheet and its answer key for each, in Classic and handwritten Notebook styles. $9 one time, or all 7 subjects for $29.99. See all prices.
Teacher? This method has a classroom pack on TeachersPayTeachers: an anchor chart, a parent letter and practice sheets with answer keys, $4. See the pack
Parents: tell your child's teacher about this guide
Parents also ask
What's the difference between an array and equal groups?
Equal groups can be in piles or circles. An array lines them up in rows and columns, which makes it easier to see.
Does it matter which is rows and which is columns?
The total is the same, but classes usually write rows first: 3 rows of 4 is 3 × 4.
Why not just memorize 3 × 4?
Memorizing comes later. The array shows what the fact means, which makes it easier to remember.
Where do arrays lead?
To area. A rectangle 3 units by 4 units is a 3-by-4 array of squares.