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Math

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.)
Community Questions
A thumbnail for: Addition and subtraction
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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!
A thumbnail for: Multiplication and division
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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.
A thumbnail for: Fractions
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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.
A thumbnail for: Measurement and data
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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!
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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!
A thumbnail for: Factors, multiples and patterns
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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.
A thumbnail for: Place value and rounding
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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.
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.

Multiplication

You know your multiplication tables (and basic division) from the 3rd grade and are ready to learn how to multiply and divide multi-digit numbers. Imagine the possibilities! This tutorial will make you unstoppable. Common Core Standard: 4.NBT.B.5

Grids and area models to visualize multiplication

Most of us learn to multiply multi-digit numbers eventually, but only a select-few actually understand what the multiplication represents. This tutorial, with the help of grids and area models, will allow you to be part of this elite group. Common Core Standard: 4.NBT.B.5

Comparing with multiplication

In this tutorial, we look at multiplication and division through the lens of comparison. For example, say that are 9 and 3 times older than your cousin. How old would your cousin be? Common Core Standards: 4.OA.A.1, 4.OA.A.2

Division

You know your multiplication tables and are getting the hang of basic division. In this tutorial, we will journey into the world of loooong division (sometimes, referred to as "long division", but that's not as much fun to say). After this tutorial, you'll be able to divide any whole number by a single digit number. You'll also see that sometimes things don't divide evenly and you'll be left with a remainder. The fun will not stop! Common Core Standard: 4.NBT.B.6

Multistep word problems

In this tutorial, we'll start to challenge you with more sophisticated multiplication and division word problems. If you understand mult-digit multiplication and long division, you have all the tools you need to tackle these. May the force be with you! Common Core Standard: 4.OA.A.3