Grade K · Counting & Cardinality
One More and One Less
See how neighboring numbers are connected by adding or removing one.
The counting sequence has structure
Every step forward in the counting sequence makes the quantity one larger. Every step backward makes it one smaller.
Use the number line
If you are on 6, one step right lands on 7 and one step left lands on 5. That means 7 is one more than 6 and 5 is one less.
Key terms
Words to know
- One more
- A quantity that has one additional item.
- One less
- A quantity that has one fewer item.
- Neighboring numbers
- Numbers immediately before and after another number.
Interactive math lab · ⭐ stars
Change it. See it. Understand it.
Move the star to a number and compare its two neighbors.
| One less | 3 |
|---|---|
| Number | 4 |
| One more | 5 |
Worked examples
See the idea in action.
3 is one less than 4; 5 is one more.
The same pattern works near 10.
Guided practice
Work through 20 questions, one step at a time.
Choose an answer, check your reasoning, then move forward. Your score updates as you go.
Which statement is true about 3 + 5 and 5 + 3?
Curriculum reference
Built as a continuous K–12 progression.
The sequence follows widely used K–12 mathematics progressions and references the Common Core mathematics framework. Explanations, examples, interactive models, and practice questions are original FreeLearnHub material.