If you're seeing this message, it means we're having trouble loading external resources for Khan Academy.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

3rd grade (U.S.)

We know you've been rocking through 2nd grade adding and subtracting all kinds of whole numbers. (up to 2 digits, right?). That's awesome! In 3rd grade math we want you to start using bigger numbers and start multiplying and dividing, too. By the way, did you know that some numbers aren’t actually “whole?” They’re “partially whole.” We call them fractions! We want you to start playing around and having fun with those, too. There's also area, perimeter, and place value to be discovered. Whew. We have so much to do and can't wait to do it with you. Let's go!
Community Questions
Addition and subtraction
In the 2nd grade you learned to add and subtract 2-digit numbers. Now we take things further by adding and subtracting three-digit numbers. This is good practice for 4th grade where you'll be expected to add or subtract pretty much any whole number!
All content in “Addition and subtraction”

Adding with regrouping within 1000

You're somewhat familar with adding, say, 17 + 12 or 21 + 32, but what happens for 13 + 19? Essentially, what happens when I max out the "ones place"? In this tutorial, we'll introduce you to the powerful tool of regrouping and why it works. Common Core Standard: 3.NBT.A.2

Using regrouping to subtract within 1000

You can subtract 21 from 45, but are a bit perplexed trying to subtract 26 from 45 (how do you subtract the 6 in 26 from the 5 in 45). This tutorial is your answer. You'll see that we can essentially "regroup" the value in a number from one place to another to solve your problem. This is also often called borrowing (although it is like "borrowing" sugar from your neighbor in that you never give it back). Common Core Standard: 3.NBT.A.2