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Activity
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Illustrative Mathematics

A Midpoint Miracle

For Teachers 9th - 12th Standards
Young geometers develop one of the fundamental properties of quadrilaterals (connecting side midpoints gives a parallelogram) in this short but thought-provoking exercise. Using a combination of hands-on techniques and abstract algebraic...
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Lesson Plan
EngageNY

How Do Dilations Map Angles?

For Students 9th - 10th Standards
The key to understanding is making connections. Scholars explore angle dilations using properties of parallel lines. At completion, pupils prove that angles of a dilation preserve their original measure. 
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Lesson Plan
Curated OER

Perpendicular Bisector of a Line Segment

For Teachers 9th - 12th Standards
High Schoolers investigate the perpendicular bisector of a line segment. They use Cabri Jr. to construct the perpendicular bisector of a segment. The dynamics capabilities of Cabri Jr. allow your learners to observe the lengths of the...
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Worksheet
Curated OER

Points, Lines and Planes

For Students 10th
In this points, lines and planes worksheet, 10th graders solve and complete 9 various types of problems. First, they name the planes that intersect a figure shown. Then, students determine the points that are collinear and coplanar in...
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Lesson Plan
Curated OER

Applying Proportionality in Scale Drawings

For Teachers 6th
Sixth graders examine a blue print and discuss the reasoning behind using blue prints. In this proportionality lesson,  students collaborate with their teammates to create a scale drawing. Once that is complete, 6th graders write a...
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Lesson Plan
Curated OER

Geometry in Tessellations

For Teachers All
Students examine tessellations and their geometric properties. Students also develop a better understanding of lines, planes, angles, and polygons.
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Unit Plan
Mathematics Vision Project

Circles: A Geometric Perspective

For Teachers 10th - 12th Standards
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
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Printables
Houghton Mifflin Harcourt

Unit 6 Math Vocabulary Cards (Grade 3)

For Teachers 3rd
A set of 49 math vocabulary cards ranges from angle to irregular polygon to parallel lines. Each sheet contains two cards: one with the word printed in bold text and the other with the definition.
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Lesson Plan
EngageNY

Construct and Apply a Sequence of Rigid Motions

For Teachers 9th - 12th Standards
Breaking the rules is one thing, proving it is another! Learners expand on their previous understanding of congruence and apply a mathematical definition to transformations. They perform and identify a sequence of transformations and use...
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Lesson Plan
EngageNY

Similarity and the Angle Bisector Theorem

For Teachers 9th - 10th Standards
Identifying and verifying reproducible patterns in mathematics is an essential skill. Mathematicians identify the relationship of sides when an angle is bisected in a triangle. Once the pupils determine the relationship, they prove it to...
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Assessment
EngageNY

Mid-Module Assessment Task: Grade 8 Module 2

For Students 8th Standards
It's time for a concept check! Check for student understanding over the three types of rigid transformations. The assessment follows the first 10 lessons in this series and to test pupils' proficiency of these concepts. Individuals...
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Printables
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Houghton Mifflin Harcourt

Unit 6 Math Vocabulary Cards (Grade 4)

For Students 4th
In need of math vocabulary cards? Use a set of 66 vocabulary cards with topics focused mostly on geometry terms. Each sheet has two cards on it. The top half has the word printed in bold text, while the bottom half has the card with the...
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Lesson Plan
EngageNY

Solve for Unknown Angles—Transversals

For Teachers 9th - 10th Standards
Lead your class on an exciting journey through the world of math as they review geometry facts and solve for unknown angles. They learn how to use auxiliary lines and congruent angles to correctly complete each practice problem...
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Lesson Plan
EngageNY

Complex Numbers as Vectors

For Teachers 11th - 12th Standards
Show your math class how to use vectors in adding complex numbers. Vectors represent complex numbers as opposed to points in the coordinate plane. The class uses the geometric representation to add and subtract complex numbers and...
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Assessment
CCSS Math Activities

Patchwork

For Students 9th - 12th Standards
Patch up any misconceptions about writing functions. Scholars undertake a performance task that has them first examine a pattern in patchwork cushions. They represent the patterns in triangular and rectangular blocks using a table and as...
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Worksheet
Curated OER

Arcs and Chords

For Students 10th
In this arcs and chords learning exercise, 10th graders solve 6 different problems related to determining the arcs and chords of various circles. First, they define the 3 theorems that state the relationships between arcs, chords, and...
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Lesson Plan
Curated OER

Regents Exam Questions GG 10: Solids

For Teachers 10th - 12th
In this solids worksheet, students identify true statements that match a given solid. They identify parallel lines. This two-page worksheet contains four problems. Answers are listed on the last page.
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Lesson Plan
Curated OER

Math: Symmetry and Similarity

For Teachers 6th - 8th
Pupils describe the differences between congruence and similarity. After explaining the motions that indicate congruency of two shapes, they complete worksheets to draw lines of symmetry and similar shapes. With straws and twist ties,...
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Lesson Plan
Curated OER

Reflections

For Teachers 5th
Fifth graders create a reflection of a poygon using a Mira. They discover that a line connecting a vertiex of a polygon and the corresponding vertex of its reflection is perpendicular to the line of reflection. Students create a glide...
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Lesson Plan
Curated OER

Quilt Geometry

For Teachers 7th
Seventh graders explore lines of symmetry, congruent polygons and patterns. They listen to "The Seasons Sewn," observe a PowerPoint presentation, and identify congruent polygons and visual patterns. Through an internet activity, 7th...
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Lesson Plan
Curated OER

Drawing Figures

For Teachers 3rd
Third graders draw shapes that are congruent. In this congruency lesson, 3rd graders use grid paper to draw letters and figures and their congruent partners. They complete a worksheet while working in a whole class setting with the...
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Worksheet
Curated OER

Tests for Parallelograms

For Students 10th
In this tests for parallelograms worksheet, 10th graders solve 7 various types of geometry problems that include parallelograms. First, they determine if each quadrilateral is a parallelogram and justify their answers. Then, students...
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Worksheet
Curated OER

Indirect Euclidean Proofs

For Students 10th
In this Euclidean proofs activity, 10th graders solve 10 different problems that include completing indirect Euclidean proofs. First, they write a statement for each of the reasons listed on the sheet of proofs. Then, students solve the...
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Worksheet
Curated OER

Parallelograms

For Students 10th
In this parallelograms worksheet, 10th graders identify and describe a quadrilateral, a diagonal, and a parallelogram in 7 different problems. First, they find the values of x, y, and z in each quadrilateral to prove that it is a...