Grade 3 math
Lessons commonly taught in grade 3, each with worked examples, practice problems, and complete solutions. Topics often span more than one grade, so you may see a lesson listed under a neighboring grade too.
17 lessons · 50 standards
Whole Numbers & Operations
- Adding and Subtracting Large Numbers
How to add and subtract multi-digit numbers in columns, what carrying and borrowing actually do, and how to check an answer by estimating or by working backwards.
- Times as Many: Comparison and Multi-Step Word Problems
How to read a times-as-many comparison, tell it apart from a more-than comparison, and work a multi-step word problem by writing an equation for each step.
- Patterns in the Times Table
The patterns hiding in the addition and multiplication tables, and the reason each one is there — so the table can be rebuilt rather than only memorized.
- Place Value and Rounding Whole Numbers
What each digit in a number is worth, why every place is ten times the one to its right, how to write a number in expanded form, and how to round to any place.
- What Is Division? Sharing, Grouping and Missing Factors
The two questions division answers, how it undoes multiplication, why every division is a missing-factor problem, and how to find an unknown in an equation.
- What Is Multiplication? Equal Groups and Arrays
What a product means, how equal groups and arrays show it, why the order of the factors does not matter, and how the properties make the times tables shorter to learn.
Fractions
- Comparing Fractions: Which One Is Bigger?
Four ways to compare fractions: same bottom number, same top number, a common denominator, and cross multiplying. With bar models and worked examples.
- Equivalent Fractions: Same Amount, Different Numbers
What equivalent fractions are, how to find them by multiplying or dividing top and bottom by the same number, and how to check two fractions are equal.
- Fractions on a Number Line: Plotting and Reading Them
How to place a fraction on a number line by splitting each whole into equal parts, how to read one off, and why the number line makes fractions easier to order.
- What Is a Fraction? Equal Parts of a Whole
What the top and bottom numbers mean, why the parts must be equal, how a fraction is built from copies of a unit fraction, and when a fraction equals a whole number.
Measurement & Data
- Bar Graphs and Picture Graphs
How to read a scaled bar graph and a picture graph, why the key or scale must be checked first, and how to measure lengths to build a data set of your own.
- Measuring Mass and Liquid Volume
What grams, kilograms, milliliters and liters measure, how to pick a sensible unit, how to read a scale between its marks, and how to estimate before measuring.
- Telling Time and Working Out Time Intervals
How to read a clock to the nearest minute, why the two hands use different scales, how to find how long something lasted, and how to add and subtract times.
Geometry
- Area of a Rectangle: Length Times Width
Why the area of a rectangle is length times width, how to find a missing side, why area uses square units, and how to handle L-shaped figures.
- Perimeter: The Distance Around a Shape
What perimeter means, how to find it for any shape by adding the sides, the rectangle shortcut, and how to work backwards from a known perimeter.
- Sorting Shapes into Categories
Why shapes belong to more than one group at once, what makes a square also a rectangle, and how splitting a shape into equal parts gives each part a fraction name.
- Splitting a Rectangle to Find Its Area
How cutting a rectangle into two smaller rectangles keeps the total area the same, and how that turns a hard times fact into two facts you already know.
Standards covered
- CCSS.MATH.CONTENT.3.G.A.1
- CCSS.MATH.CONTENT.3.G.A.2
- CCSS.MATH.CONTENT.3.MD.A.1
- CCSS.MATH.CONTENT.3.MD.A.2
- CCSS.MATH.CONTENT.3.MD.B.3
- CCSS.MATH.CONTENT.3.MD.B.4
- CCSS.MATH.CONTENT.3.MD.C.5
- CCSS.MATH.CONTENT.3.MD.C.5a
- CCSS.MATH.CONTENT.3.MD.C.5b
- CCSS.MATH.CONTENT.3.MD.C.6
- CCSS.MATH.CONTENT.3.MD.C.7
- CCSS.MATH.CONTENT.3.MD.C.7a
- CCSS.MATH.CONTENT.3.MD.C.7b
- CCSS.MATH.CONTENT.3.MD.C.7c
- CCSS.MATH.CONTENT.3.MD.C.7d
- CCSS.MATH.CONTENT.3.MD.D.8
- CCSS.MATH.CONTENT.3.NBT.A.1
- CCSS.MATH.CONTENT.3.NBT.A.2
- CCSS.MATH.CONTENT.3.NBT.A.3
- CCSS.MATH.CONTENT.3.NF.A.1
- CCSS.MATH.CONTENT.3.NF.A.2
- CCSS.MATH.CONTENT.3.NF.A.2a
- CCSS.MATH.CONTENT.3.NF.A.2b
- CCSS.MATH.CONTENT.3.NF.A.3
- CCSS.MATH.CONTENT.3.NF.A.3a
- CCSS.MATH.CONTENT.3.NF.A.3b
- CCSS.MATH.CONTENT.3.NF.A.3c
- CCSS.MATH.CONTENT.3.NF.A.3d
- CCSS.MATH.CONTENT.3.OA.A.1
- CCSS.MATH.CONTENT.3.OA.A.2
- CCSS.MATH.CONTENT.3.OA.A.3
- CCSS.MATH.CONTENT.3.OA.A.4
- CCSS.MATH.CONTENT.3.OA.B.5
- CCSS.MATH.CONTENT.3.OA.B.6
- CCSS.MATH.CONTENT.3.OA.C.7
- CCSS.MATH.CONTENT.3.OA.D.8
- CCSS.MATH.CONTENT.3.OA.D.9
- CCSS.MATH.CONTENT.4.MD.A.2
- CCSS.MATH.CONTENT.4.MD.A.3
- CCSS.MATH.CONTENT.4.NBT.A.1
- CCSS.MATH.CONTENT.4.NBT.A.2
- CCSS.MATH.CONTENT.4.NBT.A.3
- CCSS.MATH.CONTENT.4.NBT.B.4
- CCSS.MATH.CONTENT.4.NF.A.1
- CCSS.MATH.CONTENT.4.NF.A.2
- CCSS.MATH.CONTENT.4.NF.B.4a
- CCSS.MATH.CONTENT.4.NF.B.4b
- CCSS.MATH.CONTENT.4.OA.A.1
- CCSS.MATH.CONTENT.4.OA.A.2
- CCSS.MATH.CONTENT.4.OA.A.3