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▾
3rd grade
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Addition, subtraction, estimation
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Mentally add within 1000
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Round to the nearest 10 or 100
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Add and subtract within 1000, abstract
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Multiplication
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Multiplication using rectangular arrays and equal groups, concrete and visual
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Multiplication as repeated addition
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Multiply, abstract
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Division
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Divide using equal groups
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Division using repeated subtraction
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Divide, abstract
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Fractions
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Equal shares of shapes and unit fractions
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Plot fractions on the number line
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Relating fractions to 1
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Representing whole numbers as fractions
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Comparing fractions with like numerators, denominators, or both
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Relating multiplication and division
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Missing number problems, multiplication and division
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Relating multiplication to division
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Use properties to multiply and divide
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Multiply one-digit numbers by multiples of 10
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Arithmetic patterns and problem solving
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Two-step word problems
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Patterns in addition and multiplication
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Intro to the triangular numbers
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Intro to the Fibonacci sequence
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Intro to Pascal's triangle
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Geometry
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Shape heirarchy
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Area of composite rectangles by counting unit squares
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Area and units of measure
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Area as multiplication
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Area, perimeter, and how they're related
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Time, measurement, and data
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Tell and write time, minute increments
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Measure and estimate volumes and masses
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Scaled bar and picture graphs
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Line plots with fractions
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3rd grade
›
Geometry
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Area as multiplication
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Other resources
Area of a rectangle with whole number side lengths
Lesson
YouTube videos
71900
Area of a Rectangle | How to Calculate Area of a Rectangle | Math Help with Mr. J
Math with Mr. J
72642
Key Skill - Find the area of a rectangle.
DrFrostMaths
Practice
Khan Academy exercises
Area of rectangles
Khan Academy
YouTube videos
71779
Area of a Rectangle (Mastery Check) | Math Help with Mr. J
Math with Mr. J