What is a cube?
A cube is a solid shape with six same-size square faces. A toy building cube is one object, even when we can see more than one of its faces. In this lesson, each pictured cube counts as one.
This drawing shows one cube. The shaded faces help us see its three-dimensional shape.
There is 1 cube.
Count each whole cube once. Do not count its faces as separate objects.
Count one cube at a time
Say the counting numbers in order: 1, 2, 3, 4, 5. Give each cube one number. Point to or touch each cube once so you do not skip one or count it twice.
Point to the cubes from left to right. The numbers below show the counting order.
Say, “1, 2, 3.” The last number is 3, so there are 3 cubes.
Use one number for each cube. Keep the numbers in the same order every time you count.
Recognize groups from 0 to 5
A numeral tells how many cubes are in a group. Look at each numeral, then count the cubes that belong with it.
0
Zero
1
One
2
Two
3
Three
4
Four
5
Five
Zero is a number too. It names a group with no cubes.
Understand zero cubes
Zero means none. If a group has no cubes, its count is 0.
The group is empty. There are 0 cubes.
An empty group is not one cube. Count only the cubes you can see.
The last number tells how many
When you count a group, the last number you say tells how many cubes there are altogether. This is the total.
Count, “1, 2, 3, 4, 5.” The last number is 5, so the total is 5 cubes.
You do not need to start again to tell how many. Remember the last number you said.
The arrangement can change
Cubes can be in a row or in a different arrangement. If none are added or taken away, the total stays the same.
In a row
3 cubes
In a triangle
3 cubes
Count each group. Both groups have 3 cubes.
Do not guess from the shape of the group. Count the cubes to check.
Match a numeral to the cubes
To match a numeral and a group, read the numeral and count the cubes. They match when the number and the total are the same.
The numeral 4 matches the group because there are 4 cubes.
Look at the numeral, count the cubes, and check that the two amounts match.
Check your count
Use this careful routine: look, point, count, and tell. Make sure every cube has been counted exactly once.
- Look: Find all the cubes in the group.
- Point: Point to one cube at a time.
- Count: Say the numbers in order.
- Tell: Say how many cubes there are altogether.
For example: “I counted 1, 2, 3. There are 3 cubes.”
If you lose your place, begin again and point to each cube once. Counting slowly helps you keep track.
Notes for teachers
This resource is designed to provide clear explanations, examples, and practice for learners of different needs and levels of support. It may be used for whole-class instruction, guided practice, independent learning, review, homework, or additional reinforcement at home.