Even and Odd Numbers

Learn to identify even and odd numbers and discover the patterns they create.

Elementary15 minLesson

Definition

Even numbers can be divided by 2 with no remainder. They end in 0, 2, 4, 6, or 8.

Odd numbers cannot be divided evenly by 2. They end in 1, 3, 5, 7, or 9.

\text{Even: } 0, 2, 4, 6, 8, 10, 12, \ldots

\text{Odd: } 1, 3, 5, 7, 9, 11, 13, \ldots

Quick test: To check if a number is even or odd, just look at the last digit!

Try it now

Which number is even?

Worked Examples

Is 48 an even or odd number?

Look at the last digit

The last digit of 48 is 8 → Last digit: 8

Check if it's in the even list

Even digits are 0, 2, 4, 6, 8. Is 8 in this list? → Yes, 8 is even

Conclusion

Since 48 ends in 8, it is even → 48 is even

Answer: 48 is an even number because it ends in 8.

Common Mistakes

Thinking 0 is neither even nor odd

Why it's wrong: Zero can be confusing because it's special in many ways.

Correct: 0 IS even! It divides by 2 with no remainder: $0 \div 2 = 0$

Looking at the first digit instead of the last

Why it's wrong: It's easy to read left-to-right and check the wrong digit.

Correct: Always check the LAST digit. For 52, check 2 (not 5). For 87, check 7 (not 8).

Thinking bigger numbers must be even

Why it's wrong: Large numbers seem more "complete" but size doesn't matter.

Correct: Any size number can be even or odd. 1,000,001 is odd. 2 is even.

Interactive Visual

Range:to

Click on numbers to select them. Adjust the range to explore different values.

Interactive Sandbox

Expression Calculator

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Practice Problems

17 problems

Problem 1 of 17

Easy

Which number is even?

Why It Matters

Even and odd numbers are everywhere:

Sharing equally: Can you split 12 cookies between 2 friends? Yes, because 12 is even!
Pairing: Socks come in pairs. An even number of socks means no leftovers.
Sports: Tennis doubles needs 4 players (even). A relay race team has 4 runners (even).
Building: Brick patterns often alternate between rows.

Understanding even and odd helps with division, multiplication patterns, and problem-solving!

Real World Applications

Fair Sharing

When dividing things between 2 people, even numbers split perfectly.

Example:

You have 14 candies to share with your friend. $14 \div 2 = 7$ each. Fair!

1Try It Yourself

You have 15 stickers to share equally between 2 friends.

Can you share them fairly? If not, how many are left over?

Step 1: Write the mathematical expression

Divide: $15 \div 2$

Pairing Objects

Even numbers pair up perfectly. Odd numbers always have one left alone.

Example:

8 socks make 4 complete pairs. 9 socks make 4 pairs with 1 sock left over.

2Try It Yourself

A class has 23 students. The teacher wants them to work in pairs.

How many pairs can be formed? Will anyone work alone?

Step 1: Write the mathematical expression

Calculate pairs: $23 \div 2$

Key Takeaways

1Even numbers end in 0, 2, 4, 6, or 8 and divide evenly by 2
2Odd numbers end in 1, 3, 5, 7, or 9 and have a remainder of 1 when divided by 2
3Zero is an even number
4Even + Even = Even, Odd + Odd = Even, Even + Odd = Odd

Frequently Asked Questions

Zero is EVEN. It divides by 2 with no remainder (

0 \div 2 = 0

), and it fits the pattern: ...,

-4

-2

, 0, 2, 4, ...

Glossary

Even number: A number divisible by 2 with no remainder (ends in 0, 2, 4, 6, or 8)
Odd number: A number that has a remainder of 1 when divided by 2 (ends in 1, 3, 5, 7, or 9)
Divisible: A number is divisible by another if it divides evenly with no remainder
Remainder: The amount left over after division