Add within 1000
Adding three-digit numbers with confidence gives your child solid ground for nearly every calculation that follows. In 4th grade the numbers grow into the thousands, and the same place value thinking (knowing what each digit is worth) carries them through. It also keeps word problems about the reasoning rather than the arithmetic. You’ll see it when you total a grocery bill, add up points in a game, or plan the miles of a road trip.
In this video, your child will learn to add three-digit numbers.
The lesson stops at each question for your child's answer.
Three problems, each a little harder
Each problem is worked step by step. Your child will solve the last one before Bobby shows how.
Example 1
256 + 138 = ?
Example 2
367 + 285. Now there are 15 tens. What do we write in the tens place?
Your child's turn
548 + 376 = ?
The three key steps
- 1Ones, then tens, then hundreds.
- 210 ones make a ten.
- 310 tens make a hundred.
Mistakes to listen for
- Leaving out the extra hundred when the tens add up to 10 or more, so 352 + 175 comes out as 427 instead of 527.
- Lining up the digits from the left, so 345 + 62 gets added as 345 + 620 and comes out as 965 instead of 407.
- Splitting numbers into hundreds, tens, and ones and then dropping one part, so 238 + 145 adds up to 370 instead of 383.
The lesson shows every step, so your child sees why it works. Read our parent's guide to adding within 1,000 →
Is your child ready to practice what they've learned?
Bobby's Math Club offers unlimited practice for free.
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More 3rd grade Numbers & Place Value, with questions your child answers along the way.
Questions parents ask
Does my child need an account to watch?
No. You can watch this on any device at any time. If your child would like to practice adding within 1,000, and you'd like parent-friendly reports on your child's progress and growth, you can join Bobby's Math Club for unlimited free practice.
What happens when my child answers a question?
A right answer gets a cheer, and the lesson carries on. If your child isn't sure, they can tap "I don't know yet", and Bobby gives the answer and shows another example. Nothing is scored or stored.
Is this the same lesson that's on YouTube?
Yes. Here, the lesson stops at each question and waits for your child to answer. On YouTube, each question stays on screen for a few seconds, and then the lesson plays on.
Where can I learn more?
There's a short, kid-friendly lesson like this one for every Pre-K to 5th grade math skill, all in our video library. Our parent's guide to adding within 1,000 has more on where kids get stuck and how you can help at home. In the club, your child practices at just the right level, about five minutes a day, and you get parent-friendly reports as they grow. Learn more about how it works →
Practice adding within 1,000
Questions at your child's level, about five minutes a day, on adding within 1,000 and whatever PK-5 skills they need to develop. Unlimited practice, free forever.
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