Carrying and borrowing are ways of bundling and unbundling numbers around ten.
When the ones pass ten, as in 7 + 5, you gather ten into a bundle and carry it over; when they are too few to subtract, as in 13 − 5, you unbundle a ten.
The make-ten trick helps: for 8 + 5, add 2 to reach 10, then add the leftover 3.
Here you slide the two numbers and watch the blocks form a ten and break apart.
Let's Make 10!
🧱 What is Carrying?
①How do we calculate 7 + 5 = 12?
②When ones exceed 10, group them into 10
③1 ten + 2 ones = 12!
④This is called "carrying"
Try Carrying
7
5
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Carrying process: making a group of 10 when adding two numbers
💡 Make-10 Strategy
①If the sum exceeds 10, group 10
②7 + 5: add 3 to 7 to make 10, then add the remaining 2
③Make a ten → "carry"!
④Filling up to 10 from the bigger number is easy
Try Borrowing
13
5
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Borrowing process: unbundling a 10 to subtract
📦 What is Borrowing?
①In 13 − 5, you can't subtract 5 from 3 in the ones place
②Unbundle one ten → now 13 ones!
③13 − 5 = 8
④Unbundling a ten to subtract is "borrowing"
Summary
Carrying
Ones sum ≥ 10 → make a ten
e.g., 8 + 5 = 13 → 1 ten + 3 ones
Borrowing
Can't subtract in ones → unbundle a ten
e.g., 12 − 7 → unbundle 10 to make 12 ones, subtract 7 → 5
Make-10 Strategy
8 + 5 = 8 + 2 + 3 = 10 + 3 = 13
Make 10 first, then add the rest
🎯 Remember!
①Group 10 → 1 ten (carrying)
②Unbundle 1 ten → 10 ones (borrowing)
③Making 10 is the key strategy
④Practice with fingers!
⑤Great job! Next: shapes!
Examples and Unit Test
Example 1
What is 7 + 6? (addition with carrying)
1
First make 10 by adding 3 to 7 (using 3 of the 6).
2
Add the remaining 3: 10 + 3 = 13.
▸ 13
Carrying means making 10 first, then adding what is left.
Example 2
What is 15 − 8? (subtraction with borrowing)
1
You cannot subtract 8 from the 5 in the ones place.
2
Unbundle the ten to make 15 ones, then 15 − 8 = 7.
▸ 7
Borrowing means unbundling a ten when the ones are too few to subtract.