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4th grade (U.S.)

4th grade is the time to start really fine-tuning your arithmetic skills. Not only will you be a multi-digit addition and subtraction rockstar, but you'll extend the multiplication and division that you started in 3rd grade to several digits. You'll also discover that you sometimes have something left over (called a "remainder") when you divide. In 3rd grade you learned what a fraction is. Now you'll start adding, subtracting, multiplying, and comparing them. You'll also see how they relate to decimals. On other fronts, you'll learn how to convert between different units (which is super important when comparing the size and speed of robot unicorns in different countries) and continue your journey thinking about various shapes in two dimensions. Some of the foundational concepts of geometry (like lines, rays and angles) also get introduced. As always, we'll round this out with a healthy dose of applied word problems and explorations of number patterns and properties (including the ideas of factors, multiples and prime numbers). The fun must not stop! (Content was selected for this grade level based on a typical curriculum in the United States.)
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Addition and subtraction

Fourth grade is the time to really fine-tune your addition and subtraction skills to the point that you can add and subtract pretty much any multi-digit, whole number!

Multiplication and division

Let's continue on the multiplication and division adventure that was started in third grade--now we'll think about these operations with multi-digit numbers and discover that we sometimes have something left over, or a remainder, when we divide.

Fractions

In 3rd grade, you got a basic conceptual understanding of what a fraction is. Now we dig deeper by comparing fractions and starting to perform operations on them. We also see how they relate to decimals.

Measurement and data

When we measure anything, we do it in human-defined 'units'. Different units were defined in different places and for different scales. Let's think about how to convert between the them! We'll also get our feet wet in angles and continue thinking about perimeter and area!

Geometry

The basic foundations of geometry-lines, rays, angles--will be explored! On top of that, we will start to see how various shapes can be classified!

Factors, multiples and patterns

We know that 3x2x5 = 30. So 2, 3, and 5 are factors of 30. 30 is a multiple of each of 3, 2, and 5. If a number only has itself and 1 as factors, then the number is "prime". Don't worry, this is explained in much more depth in the tutorials in this topic. We will also explore some mathematical patterns.

Place value and rounding

We've been exploring place value for several years now, but now we make sure that we **really** get how one place relates to another. We then use this deep understanding for understanding the conventions for rounding.
Measurement and data
When we measure anything, we do it in human-defined 'units'. Different units were defined in different places and for different scales. Let's think about how to convert between the them! We'll also get our feet wet in angles and continue thinking about perimeter and area!
All content in “Measurement and data”

Metric and U.S. customary units intro

The International System of Units used today is based on the metric system. The United States, however, likes to dance to a different drummer and still uses the old British Imperial System (U.S. customary system) for most of its measuring. This tutorial will introduce you to both for measuring distance, volume, weight and time. Common Core Standard: 4.MD.A.1

Unit conversion

When you first started measuring things in units in 2nd grade, you saw that you might want to you different units depending on the scale, application or culture that you are in. Well, you could imagine that you'd want to convert from one unit to another as well. For example, say you walked 2 kilometers. How many meters would that be? Common Core Standard: 4.MD.A.1