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Lesson Plan
Curated OER

Obtuse Triangles

For Teachers 4th
Fourth graders explore obtuse triangles. For this geometry lesson, 4th graders make obtuse triangles with paper and scissors. They determine how to find the center of their triangle.
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Worksheet
Curated OER

Triangles

For Students 3rd - 4th
In this triangles learning exercise, students identify 3 triangles by the length of their sides and 3 triangles according to their internal angles.
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Lesson Plan
Curated OER

Equilateral Triangles

For Teachers 4th - 5th
Students examine the attribute of equilateral triangles. In this equilateral triangle lesson, students examine a number of paper triangles to determine how they are classified. They determine how triangles are depicted in Navajo rugs.
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Lesson Plan
Curated OER

Nets And Surface Area

For Teachers 4th - 6th
Upper graders investigate how to find the surface area when using two-dimensional shapes. They conduct an investigation in groups while working sample problems given during class discussion with the teacher. They also review how to...
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Lesson Plan
Curated OER

Similar and Congruent Triangles

For Teachers 2nd - 4th
Learners create and classify different types of triangles using an online geo-board. They explore the concepts of similar and congruent as they discover how to draw similar and congruent triangles.
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Lesson Plan
Curated OER

Triangle Attributes and Measures

For Teachers 7th
Seventh graders explore the concept of triangles. In this triangles lesson, 7th graders sort triangles according to various attributes such as acute, obtuse, isosceles, or equilateral. Students find the area and perimeter of triangles.
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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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Worksheet
Curated OER

Constructions and Angles

For Students 6th - 10th
In this triangle constructing and classifying worksheet, students read through a tutorial on triangles and angles. Then, students complete 17 exercises in which they answer questions about angles and triangles. By clicking on the "Check"...
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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 lesson, 5th graders define the different attributes of 3 types of triangles and sort them by descriptions and comparisons. Students...
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Lesson Plan
Curated OER

Triangles Introduction

For Teachers K - 3rd
Students explore geometry by drawing various shapes in class. In this triangle characteristics lesson, students identify the attributes that classify a shape as a triangle and practice using their bodies to create triangles in class....
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Lesson Plan
Curated OER

Classifying Polygons

For Teachers 1st - 3rd
Students study polygons. In this math lesson, students play a game in which they learn the classification system for polygons. Students identify the properties of quadrilaterals.
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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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Worksheet
Curated OER

Types of Triangles

For Students 4th - 5th
In this math worksheet, students classify the listed triangles and practice labeling them correctly. The definition of each type is necessary prerequisite knowledge.
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Lesson Plan
Curated OER

Try An Angle

For Teachers 5th
Fifth graders classify the different triangles by sides and angles. They discover how many different ways they can arrange 2, 3, 4 ...7 tangram pieces to create triangles. They classify and label the six triangles on their pattern sheet.
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Lesson Plan
Curated OER

Pythagorean Theorem

For Teachers 6th - 8th
Students engage in a study of the Pythagorean Theorem to classify the hypotenuse of a triangle. The teacher uses examples from the lesson to aid students in comprehension of solving problems that involve problem solving. They create a...
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Lesson Plan
Curated OER

Pythagorean Theorem

For Teachers 9th - 12th
Learners are introduced to the Pythagorean theorem. They use three different activities that give students the opportuntiy to observe triangles, and use the Pythagorean theorem and practice different ways of determining areas of...
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Lesson Plan
Curated OER

Roundup Shapes

For Teachers K
Shapes are all around us! Kindergartenrs identify shapes in their world and guess the shape being described. They participate in a shape hunt.
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Lesson Plan
Curated OER

Circles, Rectangles, Squares, Triangles

For Teachers K
Students identify, compare and classify the various shapes. For this shapes lesson, students listen to descriptions of shapes with words such as sides, angles, congruent, and parallel. Students then give the teacher examples of shapes...
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Worksheet
Curated OER

Special Segments is a Triangle

For Students 10th
In this geometry worksheet, 10th graders examine the special segments that occur in a triangle.  The three page worksheet contains twenty-five problems.  Answers are not included. 
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Lesson Plan
Curated OER

Quandaries, Quagmires, and Quadrilaterals

For Teachers 3rd - 5th
Students classify, flip, slide, and turn a quantity of quadrilaterals.
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Worksheet
Curated OER

Informal Geometry

For Students 8th - 12th
Middle and high schoolers solve and complete 29 various types of problems. First, they match each name with its correct formula. Then, students find the length of the missing side and the distance between the two points given. In...
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Lesson Plan
Ohio Department of Education

Describing and Creating Plane Figures - Grade One

For Teachers K - 2nd Standards
Young mathematicians draw, create, and describe different shapes using triangles. They discuss attributes of the original and created shapes. Pupils classify the created shapes and draw and write in mathematics journals to communicate...
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Interactive
Curated OER

Shapes and Angles

For Students 4th
Are your geometry whizzes learning about angles and shapes? This online worksheet gives 10 multiple choice questions based on images and word problems. Concepts include deducting angle degree, classifying shapes, and identifying angle...
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Lesson Plan
Curated OER

Fractals

For Teachers 10th - Higher Ed
Pupils explore the concept of fractals. In this fractal lesson plan, students use applets to explore Koch's Snowflake, Sierpinski's Triangle, and other fractals. Pupils develop these concepts through exploration and teacher guided...