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Lesson Plan
Illustrative Mathematics

Are These Right?

For Teachers 3rd - 5th Standards
Is that a right triangle or a wrong triangle? Young mathematicians look at eleven different shapes and use a measuring tool of their choice to determine which triangles have right angles. Consider cutting out sets of the shapes to...
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Lesson Plan
EngageNY

The Angle-Angle (AA) Criterion for Two Triangles to Be Similar

For Teachers 9th - 10th Standards
What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...
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Unit Plan
Virginia Department of Education

Classifying Angles

For Teachers 4th - 8th Standards
Don't be obtuse, this geometry unit is the just the right resource for educating the acute young minds in your class. From classifying and measuring angles, to determining the congruence of shapes, this resource covers a wide range of...
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Assessment
Mathed Up!

Angles

For Students 6th - 8th Standards
What does a geometric farmer drive? A protractor, of course! A set of assessment worksheets prompts learners to use a protractor as they measure angles, name angles, and identify lines. Use the video as a way to introduce the concepts. 
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Activity
Big Kid Science

Measuring Shadows Using an Ancient Method

For Teachers 8th - 12th Standards
How did ancient peoples determine the height of really tall objects? Young scientists and mathematicians explore the concept of using shadows to measure height in a hands-on experiment. Paired pupils measure shadows, then calculate the...
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Lesson Plan
National Security Agency

Classifying Triangles

For Teachers 4th - 8th Standards
Building on young mathematicians' prior knowledge of three-sided shapes, this activity series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy...
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Unit Plan
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Mathematics Vision Project

Similarity and Right Triangle Trigonometry

For Teachers 10th - 12th Standards
Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...
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Lesson Plan
EngageNY

Special Lines in Triangles (part 1)

For Students 9th - 10th Standards
Allow your pupils to become the mathematicians! Individuals explore the properties of a midsegment of a triangle through construction and measurement. Once they figure out the properties, learners use them to draw conclusions.
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Lesson Plan
EngageNY

The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar

For Students 9th - 10th Standards
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice verifying...
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Unit Plan
Mathematics Vision Project

Geometric Figures

For Teachers 10th - 12th Standards
Logical thinking is at the forefront of this jam-packed lesson, with young mathematicians not only investigating geometric concepts but also how they "know what they know". Through each activity and worksheet, learners wrestle with...
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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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Lesson Plan
Las Cumbres Observatory

The Cosmic Distance Ladder: Parallax

For Teachers 11th - 12th
Scientists don't have a ruler long enough to measure to the stars, so they rely on math. Scholars learn to calculate the distance from Earth to a star using the parallax method. They use angle measures from different perspectives to...
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Lesson Plan
EngageNY

Scale Drawings

For Students 9th - 10th Standards
Are you searching for a purpose for geometric constructions? Use an engaging approach to explore dilations. Scholars create dilations using a construction method of their choice. As they build their constructed dilation, they strengthen...
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App
Krzysztof Haft-Szatynski

Move the Turtle

For Students 1st - 9th
Turtles are not known to be speedy movers, but have you ever tried to get them to move in a specific direction? How about getting them to move in a perfect circle? With this app, young computer programmers have to be on their toes to...
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eBook
Savvas Learning

Saxon Math 5/4

For Teachers 3rd - 5th Standards
You'll never have to search for another worksheet again after downloading this extensive collection of Saxon math materials. With over 600 pages of example problems and skills practice exercises, this is a must-have resource for any...
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Lesson Plan
Dick Blick Art Materials

Start with a Circle...

For Students K - 12th
The Golden Ratio. The Divine Proportion. Yup. It's math and art blended into one colorful activity. Young artists combine colored tissue paper circles and parts of circles to create geometric patterns. As a bonus, kids get to figure out...
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Lesson Plan
Pyro Innovations

Get into Shape

For Teachers K - 1st Standards
Shapes are so fun! Little ones explore, identify, and create shapes using tangrams or pattern blocks. The activity is intended to stimulate critical thinking while engaging learners through play and shape identification. Each child will...
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Lesson Plan
Curated OER

Sphere Dressing

For Students 7th - 10th Standards
Geometric design makes a fashion statement! Challenge learners to design a hat to fit a Styrofoam model. Specifications are clear and pupils use concepts related to three-dimensional objects including volume of irregular shapes and...