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Lesson Plan
Curated OER

Tangrams

For Teachers 4th - 12th
Students construct tangram pieces. Then they make observations and explore patterns with the pieces.
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Worksheet
Curated OER

Similar Polygons

For Students 10th
In this similar polygons instructional activity, 10th graders solve and complete 20 various types of problems. First, they solve each proportion. Then, students write a ratio expressing the slope of a line through each pair of points. In...
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Lesson Plan
Curated OER

Constructions of Isosceles and Equilateral Triangles

For Teachers 4th - 9th
Young scholars explore the difference between drawing and constructing a triangle utilizing The Geometer's Sketchpad on the computer. They create, develop and script constructions for both isosceles and equilateral triangles. Each...
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Lesson Plan
Curated OER

Make a Box

For Teachers 10th - 12th
Students use specific dimensions to create a box. In this geometry instructional activity, students analyze the different properties of two and three dimensional shapes. They make conjectures and use it to solve problems.
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Lesson Plan
Curated OER

Identifying Lines of Symmetry

For Teachers 8th - 10th
Students calculate the lines of symmetry using polygons. In this geometry instructional activity, students graph, compare and estimate using collected data. They identify different attributes to the polygons based on their sides.
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Lesson Plan
Curated OER

Polygons All Around Us!

For Teachers 9th - 12th
Young scholars explore the concept of polygon properties. In this polygon properties lesson, students draw polygons with different numbers of sides such as pentagons, octagons, hexagons, etc. Young scholars identify different geometric...
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Lesson Plan
Curated OER

Tangrams

For Teachers 4th - 11th
Students construct the tangram pieces from a square paper by following directions to fold and cut. They make observations on the pieces formed and compare how they are related to each other. They explore patterns and shapes with the...
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Activity
Oswego City School District

Regents Exam Prep Center: Organizing and Venn Diagrams With Congruent Triangles

For Teachers 9th - 10th
As a resource for teachers, an activity of how to connect Venn Diagrams with the five methods of proving triangles congruent - SSS, SAS, ASA, AAS, HL - is explained.
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Lesson Plan
Texas Instruments

Texas Instruments: Investigate Triangles and Congruence

For Teachers 9th - 10th Standards
Students can use the TI-84 Plus family with Cabri Jr. to prove triangle congruence with SSA.
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Unit Plan
Texas Education Agency

Texas Gateway: Using Logical Reasoning to Prove Conjectures About Circles

For Students 9th - 10th Standards
Given conjectures about circles, the student will use deductive reasoning and counterexamples to prove or disprove the conjectures.
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Unit Plan
CK-12 Foundation

Ck 12: Geometry: Asa and Aas Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] In this lesson students prove two triangles are congruent with the Angle-Side-Angle and Angle-Angle-Side shortcuts. Students examine guided notes, review guided...
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eBook
Mathigon

Mathigon: Geometry: Triangles and Trigonometry: Triangles Congruence

For Students 9th - 10th Standards
This lesson focuses on triangle congruence; it shows the ways to prove that triangles are congruent.
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Unit Plan
CK-12 Foundation

Ck 12: Geometry: Sas Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] Prove two triangles are congruent with the Side-Angle-Side shortcut.
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Unit Plan
CK-12 Foundation

Ck 12: Geometry: Sas Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to the SAS Triangle Postulate and how to prove that two triangles are congruent given only information about two pairs of sides and...
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Website
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Congruence and Triangles

For Students 9th - 10th Standards
This site gives a very thorough explanation of how to tell if two triangles are congruent. Dr. Math explains why SSS, SAS, ASA determine that two triangles are congruent. The Dr. gives a few exercises for the reader to try then gives the...
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Srt Joining Two Midpoints of Sides of a Triangle

For Teachers 9th - 10th Standards
In this task, young scholars must prove that angles and triangles are congruent and that a parallel line passes through the midpoints of two sides of the larger triangle. Aligns with G-SRT.B.4.
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Unknown Type
Khan Academy

Khan Academy: Proofs With Transformations

For Students 9th - 10th Standards
Explore different ways of proving some theorems about lines and angles. Some transformations are used.
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Gpe a Midpoint Miracle

For Teachers 9th - 10th Standards
In this task, students are asked to draw a quadrilateral so that no two sides are congruent, no two angles are congruent, and no two sides are parallel. The task gives students the opportunity to prove that if we join the midpoints of a...
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Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Tile Patterns I: Octagons and Squares

For Teachers 8th Standards
Eighth graders are presented with a tile pattern showing an apparent square surrounded by four octagons. They are asked to answer a question about congruency and angle measurements, as well as prove that the interior shape is really a...
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Unit Plan
Wolfram Research

Wolfram Math World: Rectangle

For Students 9th - 10th
MathWorld provides the definition of a rectangle and the area formula of a rectangle.