How to Teach Subtraction With Regrouping (So It Finally Clicks)

Borrowing trips up a lot of kids. Here is a gentle way to teach it that builds real understanding, not just a memorized trick.

If your child can subtract 9 from 15 but freezes at 52 minus 27, you are not alone. That freeze has a name. It is called regrouping, and it is one of the first places where math stops being about single digits and starts asking kids to think in tens.

The good news is that regrouping is not hard once a child sees what is really happening. Most kids struggle because they were handed a trick ("cross out the 5, make it a 4, put a little 1 next to the 2") before the trick made any sense. In this guide we will slow down and build the idea first, then the steps will feel obvious.

Borrowing or regrouping?: They mean the same thing. Older worksheets say "borrowing." Newer ones say "regrouping" because nothing is really borrowed and given back. We will use both words so your child recognizes either one.

Start with what regrouping actually means

Every two-digit number is a bundle of tens and some leftover ones. The number 52 is 5 tens and 2 ones. Regrouping is just the moment you open one of those bundles of ten and turn it into ten single ones, so you have enough to subtract.

Here is the picture that makes it click. Imagine 52 as 5 rods of ten and 2 loose cubes. Someone asks you to take away 7 cubes. You only have 2 loose ones, so you cannot. So you break open one rod of ten. Now you have 4 rods and 12 loose cubes. Nothing changed about how much you have. You just rearranged it. And now taking away 7 is easy.

Regrouping does not change the number. It only changes how the number is dressed.

Try this before any worksheet: Grab a handful of coins or blocks. Make 32 with three groups of ten and two singles. Ask your child to take away 5. Watch them realize they have to open a group of ten. That one moment is the whole lesson. The written steps are just a way to record it.

The four steps, in plain words

Once the idea is solid, the written method is short. Line the numbers up by place value, then work from the right. Here are the steps in the words I would actually say out loud to a child.

  1. Look at the ones column first. Ask: do I have enough to subtract?
  2. If not, open one ten. Cross out the tens digit, make it one smaller, and carry those ten ones over to the ones column.
  3. Now subtract the ones. There will be enough this time.
  4. Move left to the tens column and subtract there.

Worked example: 52 - 27

  1. Ones column: 2 minus 7. Not enough. Time to regroup.
  2. Open one ten from the 5. The 5 tens become 4 tens. Those ten ones join the 2 ones to make 12.
  3. Now the ones: 12 minus 7 is 5.
  4. Now the tens: 4 minus 2 is 2.
  5. Answer: 25. Quick check: 25 plus 27 is 52. It matches, so we are right.

Always check by adding back: The answer to a subtraction problem, added to the number you took away, should give you back where you started. 25 plus 27 is 52. This one habit catches almost every mistake, and it teaches kids that addition and subtraction are two sides of the same coin.

Try it yourself

Here is a small interactive tool. Enter any two-digit subtraction and watch the regrouping happen one step at a time. Let your child press the button and narrate what changes. Doing beats watching.

The mistakes almost every kid makes (and the fix)

Mistake 1: subtracting the small digit from the big one, no matter where it is

A child sees 52 minus 27, looks at the ones, and thinks "7 minus 2 is 5" because that subtraction is easier. The result looks reasonable, so it slips by. The fix is to make regrouping feel normal, not scary. When a child expects to open a ten, they stop reaching for the easy backwards subtraction.

Mistake 2: forgetting to make the tens digit smaller

They carry the ten over to the ones but leave the tens column untouched. The fix is the physical picture again. If you opened one of your five rods, you now have four. You cannot still have five. Say it out loud every time: "I opened a ten, so I have one fewer ten now."

Mistake 3: regrouping when they did not need to

Some kids, once they learn regrouping, start doing it on every problem. The fix is step one: always ask first, "do I have enough?" Regrouping is the answer to a question, not an automatic move.

How to practice without the tears

A two-minute game: Write a two-digit number on a sticky note. Your child rolls two dice, makes a two-digit number, and subtracts it from yours (regrouping when needed). First to reach zero or below wins. Kids will happily do twenty problems this way without noticing they are practicing.

When will it finally click?

For most kids, regrouping settles in over a couple of weeks of light, regular practice, usually in second or third grade. If your child understands the "open a ten" idea but still slips on the written steps, that is normal and it is not a red flag. Keep the sessions short and warm. Confidence is doing half the work here.

What grade is subtraction with regrouping taught?

It usually starts in second grade with two-digit numbers and continues into third grade with larger numbers. Some children meet it a little earlier or later, and that is fine.

What is the difference between borrowing and regrouping?

They describe the same action. "Borrowing" is the older word. "Regrouping" is the newer word and is more accurate, because you are regrouping one ten into ten ones, not borrowing something you pay back.

Should I let my child use blocks or fingers?

Yes. Physical objects build the understanding that the written steps stand for. Let your child use them as long as they help. Most kids drop the blocks on their own once the idea is solid.

My child gets the idea but keeps making small mistakes. Is that a problem?

No. Small slips while the method is still new are completely normal. Keep sessions short, check answers by adding back, and the accuracy will follow the understanding.