Worked examples
Let's solve a few small puzzles together. Read slowly and try each one before peeking at the answer.
Example 1 — read the number
Look at this:
1 ten and 5 ones
How do we write this number? One ten is 10, and 5 ones are just 5. Together that is 15. We say "fifteen".
Example 2 — split into tens and ones
Take the number 18. How many tens and how many ones?
18 = 1 ten + 8 ones
So 18 has one ten and eight ones.
Example 3 — find on the number line
Where is 13 on the number line from 0 to 20?
It is right after 12 and just before 14. Three steps to the right of 10.
Example 4 — what comes next
What number comes right after 19? Easy — that is 20. And what comes right before 20? That is 19. Knowing the next number and the one before is super useful.
Example 5 — count by tens
Start at 10 and add one full bag.
10, 20.
If first grade wants more, add another bag and you reach 30. But for now, two bags — 20 — is enough!
Want more practice
- Try Number line to drag a number to its place.
- Try Counting tens to build numbers from ten-blocks.