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Worksheet
Curated OER

Proofs

For Students 8th - 11th
In this geometric proof worksheet, students compose 20 triangle congruency proofs. Students will decide if there is enough information in problems 1-6 to prove if any triangles are congruent. In problems 17 to 20, students use given...
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Worksheet
Curated OER

Geometry Practice: Transformations, Isometries, and Tessellations

For Students 9th - 12th
Five pages for geometry practice relating to symmetry provide mathematicians with exercises on transformations and symmetry, properties of isometries, compositions of transformations, tessellations with regular polygons, and other...
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Lesson Plan
Curated OER

2-D polygons

For Teachers 3rd - 6th
A hands-on activity uses the Zome modeling system, and helps young geometers either learn or review their knowledge of polygons. Students build as many different 2-dimensional polygons as possible: triangle, square, rectangle, pentagon,...
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Lesson Plan
EngageNY

Using Trigonometry to Determine Area

For Students 9th - 10th Standards
What do you do when you don't think you have enough information? You look for another way to do the problem! Pupils combine what they know about finding the area of a triangle and trigonometry to determine triangle area when they don't...
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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
Inside Mathematics

Rugs

For Teachers 8th Standards
The class braids irrational numbers, Pythagoras, and perimeter together. The mini-assessment requires scholars to use irrational numbers and the Pythagorean Theorem to find perimeters of rugs. The rugs are rectangular, triangular,...
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Activity
Curated OER

Inscribing a Square in a Circle

For Teachers 9th - 11th Standards
Inscribing a square in a circle brings up a number of interesting geometry topics including triangle congruence and how to prove a quadrilateral is a square. This activity is followed up by finding the area of the square and determining...
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Assessment
Concord Consortium

Circling Trains

For Students 7th - 12th Standards
And round and round the park we go! Given a description of an amusement park with the locations of three attractions connected by walkways, learners consider what happens when additional attractions join the mix by doubling the length of...
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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 lesson, 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

Review of Triangles

For Teachers 8th - 10th
Students investigate the Pythagorean Theorem. In this geometry lesson, students define angles and sides of right triangles. They calculate the area and surface area using formulas derived by the Pythagorean Theorem.
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Lesson Plan
Curated OER

Scalene Triangles

For Teachers 5th
Fifth graders identify and classify scalene, equilateral, and isosceles triangles. In this triangle activity, 5th graders define the different attributes of 3 types of triangles and sort them by descriptions and comparisons. Students...
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Interactive
Curated OER

A Trying Triangle Problem

For Students 8th - 10th
In this geometry instructional activity, learners calculate the length of the sides of a given triangle. They also find the perimeter and area of the triangles given its side values. There is an answer key with this problem.
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Lesson Plan
Curated OER

Triangle Classification

For Teachers 9th - 12th
Students classify different types of triangles. In this geometry instructional activity, students identify and use properties of triangles. They differentiate between isosceles and equilateral triangles.
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Worksheet
Curated OER

Inscribed Angles

For Students 10th
In this inscribed angles activity, 10th graders solve 13 various types of problems related to inscribed angles in geometry. First, they identify a circle illustrated and each arc of the circle. They, students find the measure of each...
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Lesson Plan
Curated OER

Geometry Straws

For Teachers 3rd - 8th
Young scholars create different angles and shapes by using different lengths of straws. In this geometry straws lesson plan, students glue straws onto paper and define what they have made.
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Lesson Plan
Curated OER

Angles in Triangles

For Teachers 8th
Eighth graders translate word problems using mathematical ideas. In this geometry lesson, 8th graders identify angles of triangles using equations and the triangle sum theorem. They create angles with a protractor and straight edge.
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Lesson Plan
Curated OER

Geometry Library

For Teachers 5th
Fifth graders write and illustrate books to make a class library of math term books. They utilize vocabulary associated with geometry to make their books. For example, one character may be, Mr. A Cute.
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Lesson Plan
Curated OER

The Building Blocks of Geometry

For Teachers 5th
Fifth graders explore geometric building blocks in the real world in order to describe the characteristics and relationships of points, lines, line segments, rays, and planes. This is the first lesson plan in a series of lessons in...
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Worksheet
Curated OER

Construct, Bisect, Duplicate: Geometry Practice with Compass and Straight Edge

For Students 9th - 12th
Geometers employ a straight edge and compass to duplicate and bisect segments and angles, construct perpendiculars, parallel lines, figures, and circles with points of concurrency. Ample practice with 65 questions across 8 worksheets. No...
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Worksheet
Curated OER

Pythagorean Theorem

For Students 8th - 9th
In this Pythagorean Theorem activity, students determine the length of a missing side of triangles. They read story problems, draw diagrams, and use the Pythagorean Theorem to solve real life problems. This one-page activity contains...
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Worksheet
Curated OER

Proofs in Coordinate Geometry

For Students 10th - 11th
For this coordinate geometry worksheet, students identify the lengths of a quadrilateral and find the slope of a line. They use proofs to identify the characteristics of given quadrilaterals. This one-page worksheet contains ten problems.
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Worksheet
Curated OER

Pre-Proof Warm-Ups

For Students 10th
In this pre-proofs worksheet, 10th graders solve and complete 10 different problems that include various proofs and their definitions. They use the diagram shown and the given information to write the direct conclusion for each case....
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Worksheet
Curated OER

Area

For Students 10th
In this area worksheet, 10th graders solve 7 various types of problems by finding the area of various shapes in geometry. First, they determine what happens to the area and perimeter of a rectangle when the length and width are doubled....
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Lesson Plan
Curated OER

ARE YOU A TRIANGULATEER?

For Teachers 3rd - 6th
Students explore about triangles and their relationship to the worlld around them. They are able to identify triangular shapes in their environment. Students are able to communicate to one another their understanding of triangles outside...