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Lesson Plan
EngageNY

Triangle Congruency Proofs (part 2)

For Teachers 9th - 10th Standards
Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...
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Lesson Plan
EngageNY

Triangle Congruency Proofs (part 1)

For Teachers 9th - 10th Standards
Can they put it all together? Ninth graders apply what they know about proofs and triangle congruence to complete these proofs. These proofs go beyond the basic triangle congruence proofs and use various properties, theorems, and...
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Lesson Plan
EngageNY

Informal Proofs of Properties of Dilations

For Teachers 8th Standards
Challenge the class to prove that the dilation properties always hold. The lesson develops an informal proof of the properties of dilations through a discussion. Two of the proofs are verified with each class member performing the...
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Unit Plan
1
1
EngageNY

Congruence, Proof, and Constructions

For Teachers 8th - 10th Standards
This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs.  Each of the almost-forty lessons is broken...
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Lesson Plan
1
1
Illustrative Mathematics

Similar Triangles

For Teachers 9th - 11th Standards
Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...
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Lesson Plan
EngageNY

Unknown Angle Proofs—Proofs of Known Facts

For Teachers 9th - 10th Standards
Lead the class in a Greek history lesson with a geometric twist. Pupils relate a short video about geometric properties to modern-day methods of solving for unknown angles. They discuss parallel line theorems and complete practice...
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Interactive
CK-12 Foundation

Proofs: Angle Pairs and Segments—The Three Angle Problem

For Students 9th - 11th
Finding the sum of the measures of three angles is easy, unless you have no clue what the measures are. Learners use an interactive diagram to see a geometric problem in a different way. A set of challenge questions takes them through...
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Lesson Plan
1
1
Illustrative Mathematics

Equal Area Triangles on the Same Base II

For Teachers 9th - 12th Standards
A deceptively simple question setup leads to a number of attack methods and a surprisingly sophisticated solution set in this open-ended problem. Young geometers of different strengths can go about defining the solutions graphically,...
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Lesson Plan
EngageNY

Review of the Assumptions (part 1)

For Students 9th - 10th Standards
What was the property again? Tired of hearing this from your pupils? Use this table to organize properties studied and as a reference tool for individuals. Learners apply each property in the third column of the table to ensure their...
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eBook
Old Dominion University

Introduction to Calculus

For Teachers 11th - Higher Ed Standards
This heady calculus text covers the subjects of differential and integral calculus with rigorous detail, culminating in a chapter of physics and engineering applications. A particular emphasis on classic proof meshes with modern graphs,...
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Lesson Plan
EngageNY

Converse of the Pythagorean Theorem

For Students 8th Standards
Discover a new application of the Pythagorean Theorem. Learners prove and apply the converse of the Pythagorean Theorem in the 17th lesson in a 25-part series. The examples ask learners to verify right triangles using the converse of the...
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Lesson Plan
Curated OER

Pythagorean Theorem by Graphic Manipulation

For Teachers 7th - 9th
There are many different ways to show a proof of the Pythagorean Theorem.  Here is a nice hands-on paper cutting activity that shows a graphic representation. You can even challenge your young Pythagoreans to come up with their own...
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Unit Plan
Radford University

Parallel Lines, Transversals, and Angles: What’s the Connection?

For Students 9th - 11th Standards
Streets, bridges, and intersections, oh my! Parallel lines and transversals are a present in the world around us. Learners begin by discovering the relationship of the angles formed by parallel lines and a transversal. They then apply...
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Assessment
Inside Mathematics

Magic Squares

For Teachers 9th - 12th Standards
Prompt scholars to complete a magic square using only variables. Then they can attempt to solve a numerical magic square using algebra. 
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Lesson Plan
1
1
NASA

Pop! Rockets

For Teachers K - 8th Standards
Off they go — launching rockets is fun. The lesson plan contains templates to build paper rockets that can be launched from a PVC pipe launcher. Individuals or groups build the rockets and determine the shapes for their fins. Included...
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Lesson Plan
Curated OER

NON-EUCLIDEAN GEOMETRY.

For Teachers 8th - 9th
Students study relationships between angles, side lengths, perimeters, areas and volumes of similar objects. In this lesson students also create and critique inductive and deductive arguments concerning congruency, similarity and the...
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Lesson Plan
Curated OER

Around the World With Geometry

For Teachers K - 2nd
Students identify shapes, create shapes, and make a pyramid, a drum, and a sail using their shapes. In this shapes lesson plan, students also identify plane and space shapes.
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Lesson Plan
Curated OER

Interactivate - Lines, Rays, Line Segments, and Planes

For Teachers 6th - 8th
Students explore lines, rays, line segments, and planes. For this math lesson, students discuss the math concepts and direct their instructor in graphing functions. Students collaborate in graphing additional functions.
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Lesson Plan
Shodor Education Foundation

Surface Area of Rectangular Prism

For Teachers 6th - 8th Standards
With this interactive lesson, learners compute the surface area of rectangular prisms. They visit an online investigation applet and record data on the provided handout. Pair this lesson with the volume lesson by the same publisher as an...
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Lesson Plan
Curated OER

Highs and Lows

For Teachers 8th - 11th
Solve problems using integration and derivatives. By using calculus, learners will analyze graphs to find the extrema and change in behavior. They then will identify the end behavior using the derivatives. Activities and handouts are...
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Lesson Plan
Curated OER

Why Doesn't SSA Work?

For Teachers 10th - 11th
Students investigate the relationship between angles and their sides. For this geometry lesson, students prove why SSA does not work as a true angle side relationship theorem.
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Lesson Plan
Curated OER

Fractals and the Chaos Game

For Teachers 9th - 12th
Students explore the concept of fractals. In this fractals activity, students play the "Chaos Game" via an applet. Students place dots on the screen to recognize that they have created Sierpinski's Triangle.
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Lesson Plan
Curated OER

How Do You Measure a Triangle?

For Teachers 4th
Fourth graders discover angles and their relationship to triangles. After a lecture/demo, 4th graders access websites and a worksheet imbedded in this plan to gain practice measuring triangles.
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Lesson Plan
Beacon Learning Center

Angles and Algebra

For Teachers 6th - 8th
Students calculate angle measure for triangles and complementary/supplementary angles. After a lecture/demo, students utilize a worksheet imbedded in this plan to gain practice.