Unit 1: Area and Surface Area

Students reason about areas of polygons and surface areas of polyhedra, building on geometric understandings developed in earlier grades.

Worksheets

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Unit

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Concept

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Practice

Set 1

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Set 2

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Advanced

Set 1

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Set 2

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What this unit covers

A Reasoning to Find Area · 3 lessons

Goals

• Reason about the area of two-dimensional figures by composing and decomposing them, using two principles: figures that match exactly have equal areas, and area is additive.

Lessons

1. Tiling the Plane
2. Finding Area by Decomposing and Rearranging
3. Reasoning to Find Area

B Parallelograms · 3 lessons

Goals

• Find the area of any parallelogram by identifying a base and the corresponding height.
• Generalize a process for finding the area of a parallelogram and write a formula.

Lessons

1. Parallelograms
2. Bases and Heights of Parallelograms
3. Area of Parallelograms

C Triangles · 5 lessons

Goals

• Find the area of any triangle by identifying a base and the corresponding height.
• Generalize a process for finding the area of a triangle and write a formula.
• Apply reasoning about triangles and parallelograms to find the area of other polygons.

Lessons

1. Triangles
2. Finding Areas of Triangles
3. Formula for the Area of a Triangle
4. Bases and Heights of Triangles
5. Polygons

D Surface Area · 5 lessons

Goals

• Recognize that surface area is the sum of the areas of all the faces of a three-dimensional figure.
• Use nets composed of rectangles and triangles to find the surface area of prisms and pyramids.

Lessons

1. What Is Surface Area?
2. Polyhedra
3. Nets and Surface Area
4. More Nets, More Surface Area
5. Distinguishing Between Surface Area and Volume

E Squares and Cubes · 2 lessons

Goals

• Use exponent notation to express areas of squares and surface areas and volumes of cubes.

Lessons

1. Squares and Cubes
2. Surface Area of a Cube

F Let’s Put It to Work · 1 lesson

Lessons

1. Designing a Tent (Optional)

Helpful to know first

The curriculum says this unit builds on these.

Grade 3 Math · Unit 2 Area and Multiplication

Open unit →

Grade 4 Math · Unit 1 Factors and Multiples

Open unit →

Grade 5 Math · Unit 2 Fractions as Quotients and Fraction Multiplication

Open unit →