Odd and even numbers
Recognise odd and even numbers
What a learner can do afterwards
- Identify whether a given number is odd or even
- Explain that even numbers can be divided into 2 equal groups
- Spot the pattern: even numbers end in 0, 2, 4, 6, or 8
1 · Read
Every number is either odd or even. A number is even if you can share it into two equal groups with nothing left over. A number is odd if one is left over when you try to share it evenly.
Ben has 7 pencils. He tries to share them into two equal piles. He gets 3 and 3, but one pencil is left over with no partner. That leftover pencil means 7 is odd.
Even for a big number like 84, you only need to check the last digit. It ends in 4, so 84 is even. A number like 37 ends in 7, so it is odd.
Even numbers split into two equal groups and end in 0, 2, 4, 6, or 8. Odd numbers always have one left over.
More to read
Properties of addition
Adding has helpful rules. Order does not change the total. So 3 plus 9 is the same as 9 plus 3.
Grouping helps too. You can add 2 plus 3 first, then add 4. The total stays the same however you group.
Place-value patterns
Place value helps with big patterns. Tens grow fast and ones grow slow. Watch which digit changes.
Try 5, 10, 15, 20. The ones flip between 5 and 0 while the tens climb. Spotting that flip helps you predict 25 next.
1.3: Topic C- Place Value
Each place has a job. Ones show singles, tens show groups of ten. The same digit means more when it moves left.
Compare 27 and 72. Both use 2 and 7, but 72 is larger because its 7 means 70. Place decides size.
Generate patterns
Numbers can make patterns too. Count by twos and you get 2, 4, 6, 8. Each step adds the same amount. That steady step is the rule.
Say the rule in your own words. Then use it to predict. If the rule is add 5, then 5, 10, 15 comes next as 20. Check by adding again.
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2 · Watch
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Where it sits
Learn first
Optional connections
18 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.