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Lesson Plan
Curated OER

Looking Through the Algebraic Lens

For Teachers 3rd - 5th
Students work with rectangles to find generalizations for adding and subtracting odd and even numbers in part one of the lesson. In part two, students use geoboards to construct polygons, look for patterns, and find a general rule.
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Lesson Plan
Curated OER

Partitioning a Hexagon

For Teachers 7th - 9th Standards
The task at hand is to partition a hexagon into two, four, and eight congruent figures. Make sure to give your wizards a sheet of triangle grid paper on which to decompose the hexagons. Have them explain which rotations, reflections, or...
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Worksheet
Curated OER

Geometry and Measurement Pre-Test

For Students 6th - 10th
Use this comprehensive pre-instruction assessment tool to focus your teaching where your class needs it most. Multiple choice questions assess your budding geometers' conceptual and vocabulary knowledge, but they do not solve any...
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Lesson Plan
Curated OER

Exploring Centers of a Triangle: Part 1

For Teachers 9th - 11th
Young scholars use problem solving skills, formal geometry, and The Geometer?s Sketchpad. They model and solve two real-world problems by constructing the in center and circumcenter of triangles.
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Lesson Plan
Curated OER

Ball and Triangle Game

For Teachers K - 8th
Learners view and discuss pictures of the Ball and Triangle Game the Penobscot Indian students in New England played. They construct cardboard versions of the game, and practice the game and keep score using beans.
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Lesson Plan
Curated OER

Dream Bedroom Floor Plan

For Teachers 9th - 10th
Students construct using Cabri software. In this geometry lesson, students convert between units and apply the correct measurements to build objects. They create the room virtually and manipulate the shapes to the desired measurements.
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Unit Plan
Curated OER

Zome System

For Teachers 4th - 6th
Get hundreds of interactive activity plans using the Zome Modeling System. Among dozens of lessons, a first exposure to similar triangles can be very visual for the learner. Here, young geometers explore the number of different shapes...
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Activity
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Illustrative Mathematics

Converse of the Pythagorean Theorem

For Teachers 7th - 9th Standards
Use the given tasks and detailed teacher's commentary to introduce your 8th graders to the Pythagorean theorem and its converse. Embedded links to information about Egyptian geometry make your presentation interesting. Consider giving...
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Activity
National Council of Teachers of Mathematics

Over the Hill

For Teachers 9th - 12th Standards
Can you hear me from there? Pupils determine the place to build a cell tower on a hill. The class uses constraints and creates a scale drawing on a coordinate system to calculate the exact location of the base of the cell tower.
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Worksheet
Curated OER

Three- and Two- Dimensional Geometry

For Students 7th
In this three- and two- dimensional geometry worksheet, 7th graders solve 12 various problems related to geometric shapes and measurement. They first use paper and a pencil to sketch the front, side, back, top and bottom views of each...
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Lesson Plan
Curated OER

Reflections in the Plane

For Teachers 9th - 12th Standards
Have your class explore the concept of reflections as they use Cabri Jr. to construct a triangle and reflect it over a line. Learners reflect shapes across the coordinate plane and across the lines y = x and y = -x.
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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
Alabama Learning Exchange

Is It a Triangle?

For Teachers 9th - 12th Standards
High schoolers explore the concept of triangle inequalities.  In this triangle inequality lesson, students cut spaghetti noodles into given lengths.  High schoolers use the noodles to complete a worksheet about triangle inequalities. ...
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Lesson Plan
Curated OER

Triangle Side Lengths and Angles Measures

For Teachers 9th - 10th
Students identify missing sides and angles. In this geometry instructional activity, students use triangular theorems to identify the missing sides. They use the Pythagorean Theorem to find the different ratios of each side.
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Lesson Plan
Curated OER

Corresponding Sides and Angles of Similar Triangles

For Teachers 9th - 10th
Students differentiate between corresponding sides ad angles of two triangles. In this geometry lesson, students identify the differences as well as the similarities between two triangles. They differentiate between similar and...
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Lesson Plan
Curated OER

Constructing Midsegments of Triangles

For Teachers 9th - 10th
Learners construct midsegments. In this geometry lesson plan, students make conjectures and apply properties of triangles to solve problems. They complete an activity on the computer.
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Lesson Plan
Curated OER

Why can't We Use SSA to Prove Triangles Congruent?

For Teachers 9th - 10th
Students investigate triangles and congruences. In this geometry lesson plan, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.
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Lesson Plan
Curated OER

Investigating the Sierpinski Triangle

For Teachers 9th - 11th
Students solve and analyze the sierpinski's triangle. In this geometry lesson, students identify properties and theorem of triangles. They solve problems involving angles and sides of triangles.
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Lesson Plan
Curated OER

Pythagorean Theorem: Triangles and Their Sides

For Teachers 8th - 10th
Young scholars investigate triangles and their relationship to each other. In this geometry lesson, students solve right triangles using the properties of the Pythagorean Theorem. They differentiate between right, acute, straight and...
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Lesson Plan
Curated OER

The Minimal Distance Point from the Vertices of a Triangle

For Teachers 9th - 10th
Young scholars calculate the distance from the vertex of a triangle to the center. In this geometry lesson, students find the shortest distance between a point and the vertex of a triangle. They relate this concept of distance to the...
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Lesson Plan
Curated OER

Orthocenter Of a Triangle

For Teachers 8th - 10th
Students find the orthocenter of a triangle. In this geometry lesson, students identify where the altitudes meet in a triangle. They use Cabri software to explore acute, obtuse and right triangles.
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Lesson Plan
Curated OER

Inscribed Right Triangles

For Teachers 7th - 9th
Students calculate the measurements of the inscribed angles of a triangle. For this geometry lesson, students relate the hypotenuse of a right triangle and the diameter of a circle to each other. They calculate the diameter of a circle...
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Lesson Plan
Curated OER

Area of Triangle using the Semi-Perimeter and Radius

For Teachers 8th - 10th
Learners investigate the properties of circles. In this geometry activity, students calculate the area and perimeter of a triangle. They identify the perimeter and radius length of a circle.
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Lesson Plan
Curated OER

Discovering Math: Concepts in Geometry

For Teachers 8th - 12th
Middle and high schoolers explore the concept of proving the Pythagorean Theorem. They research proofs of the Pythagorean Theorem. Pupils create posters of proofs, and research Greek mathematicians.