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Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy...
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Triangle Inequality Theorem
Learners use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
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Triangle Conjectures
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. For this geometry lesson, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by...
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Identifying Triangles
In this triangle worksheet, students label triangles as acute, right, obtuse, scalene, equilateral or isosceles. A reference web site is given for additional activities.
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"Alphabet City and City by Number" by Stephen T. Johnson; "Shapes, Shapes, Shapes" by Tana Hoban
Students review the definition of angles by identifying those in the classroom and putting them on a graphic organizer.
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Identify Triangles #
In this triangle worksheet, learners identify triangles as scalene, equilateral, right, obtuse, acute or isosceles. A reference web site is given for additional activities.
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Identify Triangles #3
In this triangle worksheet, learners identify triangles as obtuse, right, or acute, checking the correct answer. A reference web site is given for additional activities.
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Identify Triangles #2
In this triangle worksheet, students identify a set of triangles as either acute, right or obtuse, checking the appropriate box beneath each. A reference web site is given for additional activities.
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Identify Triangles
In this triangles worksheet, students identify triangles as either Acute, right or obtuse. A reference web site is given for additional activities.
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Identify Triangles
In this triangle worksheet, students check the correct answer, identifying triangles as either right, obtuse, acute, scalene, isosceles or equilateral. A reference web site is given for additional activities.
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Pythagorean Theorem
Students find the different ratios of a triangle. For this geometry lesson, students use the Pythagorean Theorem to solve for missing sides and angles on a right triangle. They use a robot to create a right triangle.
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Triangles
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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Types of Triangles
Students classify triangles by the length of their sides. In this geometry lesson plan, students use a white board to demonstrate the angles of various triangles. Students construct an equilateral, isosceles, and a scalene triangle.
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Easy Worksheet: Types of Triangles
In this types of triangles worksheet, students solve 6 short answer problems. Students identify the type of triangle being described according to side length or angle measure.
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Studying Special Segments in Triangles
Students investigate special segments in triangles. In this geometry lesson, students graph, compare, estimate and predict findings based on their data. They differentiate between similarity and congruence of triangles.
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Pythagorean Theorem
Students explore the history of Pythagoras and his contributions to mathematics. For this middle school geometry lesson, students use one inch tiles to investigate the Pythagorean Theorem and to find the length of the sides of a right...
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Triangle Classification
High schoolers classify different types of triangles. In this geometry lesson, students identify and use properties of triangles. They differentiate between isosceles and equilateral triangles.
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Geometry House!
Fourth graders use computer drawing tools to create a house of geometric shapes.
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Define Geometry Terms
The Common Core is intended to help all children meet high academic standards. Here is a Common Core designed lesson that is intended for learners with communication or language difficulties. The lesson is written in a narrative style...
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Pythagorean Theorem by Graphic Manipulation
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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Regents Exam Questions G.G.21: Centroid, Orthocenter, Incenter, and Circumcenter
In this triangles worksheet, learners solve 4 multiple choice problems. Students find the centroid, orthocenter, incenter, and circumcenter or various triangles.
Dick Blick Art Materials
Start with a Circle...
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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Point Comparisons
Young geometers investigate two-dimensional figures using coordinate grids. They identify polygons and draw examples of their reflection, rotation, and translation on a coordinate grid. And they complete a worksheet practicing examples...
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Our Geometic World
Young scholars walk around the neighborhood and identify various polygons and lines in buildings, nature and other objects. They design a building using various geometric patterns, shapes and lines. Students complete a descriptive...