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Teaching Regrouping (Carrying and Borrowing) Without Tears

By John Cabardo 3 min read Math Grade 2

Why 38 + 27 trips children up, how to show regrouping with real objects first, and a clear path from blocks to the written method.

Base-ten blocks showing tens and ones

Two-digit addition and subtraction with regrouping, often called “carrying” and “borrowing”, is a key grade 2 skill. It is also where many children start to feel that math is a set of mysterious rules. The fix is to make sure they understand what is actually happening before they learn the written shortcut.

It all depends on place value

Regrouping only makes sense if a child understands that in 38, the 3 means three tens, or thirty. Before starting, check: can your child tell you how many tens and ones are in 47? Can they show 52 with bundles of ten and loose ones? If not, spend some time there first. It will save a lot of frustration later.

Step 1: Use real objects

Bundle craft sticks or straws into tens with rubber bands, or use base-ten blocks if you have them. Show 38 as 3 bundles and 8 loose sticks, and 27 as 2 bundles and 7 loose sticks.

Now add them. Put the loose sticks together: 8 + 7 = 15 loose sticks. That’s more than ten, so bundle ten of them up, leaving 5 loose sticks. Now count the bundles: 3 + 2 = 5, plus the new one makes 6 bundles. Six bundles and 5 loose sticks: the answer is 65.

That moment of bundling ten ones into a new ten is exactly what “carrying the 1” means. Let your child do the bundling physically several times.

Step 2: Connect objects to the written method

Write the problem stacked, with the tens and ones lined up:

  38
+ 27
----

Do it with sticks and on paper side by side. When you bundle the ten loose sticks, write the small 1 above the tens column. Say it aloud: “Fifteen ones. That’s one ten and five ones. The five stays in the ones column, and the new ten goes over with the other tens.”

Step 3: Subtraction with regrouping

For 52 − 27, show 52 as 5 bundles and 2 loose sticks. You need to take away 7 ones, but there are only 2. So unbundle one ten: now there are 4 bundles and 12 loose sticks. Take away 7 loose sticks (5 left) and 2 bundles (2 left). The answer is 25.

On paper, this is crossing out the 5, writing 4 above it, and turning the 2 into 12. Avoid saying “borrow”. Nothing is given back! “Trade a ten for ten ones” or “regroup” describes what actually happens.

Common mistakes and what they mean

  • 38 + 27 = 515. The child added each column and wrote both answers down. They haven’t yet connected 15 ones to “one ten and five ones”. Go back to bundling.
  • 52 − 27 = 35. The child subtracted the smaller digit from the larger in each column (7 − 2 = 5). This is the most common subtraction error. Ask: “Can we take 7 away from 2?” and return to unbundling a ten.
  • Forgetting the carried 1. Encourage your child to write the small 1 clearly at the top of the tens column every time.
  • Misaligned digits. Squared paper keeps tens and ones in their columns.

A practice sequence

  1. Two-digit addition with no regrouping (32 + 25).
  2. Addition where the ones add to more than 9 (38 + 27).
  3. Subtraction with no regrouping (58 − 23).
  4. Subtraction that needs a trade (52 − 27).
  5. Mixed sheets, where children must decide whether regrouping is needed.

Our addition worksheet maker and subtraction worksheet maker both have a Stacked layout that lines up tens and ones for exactly this kind of practice. Set the range to 10–99 for two-digit problems, and use the answer key so your child can check each row as they go.

Estimate and check

Before calculating, round: 38 + 27 is about 40 + 30 = 70. An answer of 65 is close, while 515 clearly isn’t. For subtraction, check by adding back: 25 + 27 should give 52. Building this habit now pays off for years.

Most children need several weeks of short, regular practice before regrouping becomes automatic. Keep returning to the sticks whenever the written method stops making sense.

Put it into practice