Adding numbers up to a million
In 4th grade, children learn to add whole numbers up to a million on paper, such as 46,372 + 28,519, by lining up the places and regrouping when a column makes 10 or more.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
Try these with your child
These are real questions from our 4th grade practice. Tap the speaker to hear one read aloud, or the light bulb for a hint, and talk about the answer together.
Question 1 of 3
A beach crew picked up 1,874 bottle caps on Saturday and 2,153 on Sunday. How many bottle caps did the crew pick up in all?
- 3,927
- 4,027
- 3,974
Why this matters
Adding big numbers with ease frees your child to think about what a longer problem is asking, instead of getting stuck on the arithmetic. These sums sit inside much of what comes next: multi-step story problems, measurement, and area and perimeter. In 5th grade, the same lining up of places is how your child adds decimals, such as 12.5 + 3.75. And at home, it is how you total a receipt or a road trip.
Up next is subtracting numbers up to a million, which uses the same lined-up places in a new way.
Where kids can get stuck
- Lining numbers up by their left edges instead of by place, so 2,375 + 418 comes out as 6,555 instead of 2,793.
- Forgetting to add a regrouped ten, so 4,568 + 1,375 comes out as 5,933 instead of 5,943.
- Writing each column’s whole total instead of regrouping, so 658 + 275 becomes 81,213 instead of 933.
How you can help
- Look up the populations of two nearby towns, such as 24,817 and 38,509, and have your child add them in a column to find how many people live in both.
- Plan a road trip on paper. If one leg is 1,248 miles and the next is 1,376, ask your child for the total, and to point to each place where they regrouped.
- Keep a running total for a family goal, such as steps walked or pages read this month. Each evening, your child adds the day’s number to the total in a column and says the new total aloud.
Bobby's Math Club offers free practice that grows with your child.
Questions parents ask
Why does my child still use other ways to add?
Because some sums are quicker in your head. For 4,999 + 2,350, thinking 5,000 + 2,349 = 7,349 beats writing columns. Columns are the dependable tool for numbers like 46,372 + 28,519, where there is too much to hold in mind. Knowing both lets your child look at the numbers first and pick the way that fits.
What does fluently mean for adding big numbers?
It means your child adds accurately, with a reasonable amount of effort, and knows how to check the answer. It does not mean working at top speed. Fluent looks like your fourth grader adding 3,456 and 2,789 to get 6,245, then glancing back and seeing that about 3,000 plus about 3,000 is 6,000, so the answer makes sense.
Should my child say carry or regroup?
Either word is fine, since they name the same trade. "Regroup" says what really happens: 10 ones become 1 ten, or 10 tens become 1 hundred. Whatever word your child uses, ask what the small 1 stands for. In 4,568 + 1,375, the 1 written above the tens column is the ten made from 8 + 5 = 13 ones.
Make learning math fun
Bobby's Math Club turns 4th grade math practice into something fun to do together.
- Free, unlimited practice for every child in your family
- Practice that starts where your child is and grows with them
- Level-ups, badges, and a cheer for every win
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.
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Join the clubNote for teachers: This skill is covered by Common Core math standard 4.NBT.B.4: “Fluently add and subtract multi-digit whole numbers using the standard algorithm.” Learn how Bobby's Math Club can help your students grow. (Common Core 4.NBT.4)