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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
Measurement and geometry
In 2nd grade, you learned to measure lengths. Now we can measure the length around the edge of an object (perimeter) and how much "space" something takes up on a flat surface (area).
All content in “Measurement and geometry”

Perimeter

Have you ever wondered how much fencing you need to surround a plot of land? No? Well, you should still go through this tutorial just in case. You'll learn all about how to think about and calculate perimeter--essentially the length of the boundary of a figure.