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Common Geometric Figures
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons.
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Triangle Conjectures
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In this geometry instructional activity, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles...
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Quadrilaterals
In this geometry worksheet, 10th graders solve problems with quadrilaterals. They calculate the sum of the angles, find missing angles and identify properties of quadrilaterals. There are 16 questions with an answer key.
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Application of Delta-Epsilon Definition of the Limit
Young scholars create a Hexaflexagon using a formula. In this calculus lesson plan, students apply the definition of delta epsilon as it relates to limit to create a shape using creases. They relate the same rule to triangles and...
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If You Can’t Stand the Heat
Young scholars design and build their own solar cooker. In this math lesson, students determine the relationship between the angles of the sun, reflection and cooking time of the solar cooker. They test their project, collect data...
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Strongest Polygon
Students define and identify shapes by name. In this geometry lesson, students construct, identify and compare polygons based on the number of sides. They classify each shape based on their angle sum theorem.
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Inscribed Quadrilaterals and Parallelograms
Students differentiate between inscribed quadrilaterals and parallelograms. For this geometry lesson, students identify the shaped of the polygons when it is inscribed inside of a circle. They calculate the missing angles of the...
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Application of Delta-Epsilon Definition of the Limit
Students investigate the concept of a Limit and how it is used in a variety of problematic situations. They fold paper to help illustrate how to form equilateral triangles and explain how all the angles are the same. The lesson includes...
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Congruence Criteria for Triangles—SAS
Looking for a different approach to triangle congruence criteria? Employ transformations to determine congruent triangles. Learners list the transformations required to map one triangle to the next. They learn to identify congruence...
Willow Tree
The Pythagorean Theorem
There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...
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Review of the Assumptions (part 2)
Is the amount of information getting overwhelming for your geometry classes? Use this strategy as a way to organize information. The resource provides a handout of information studied in relation to triangle congruence. It includes a...
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The Truth About Triangles And Proofs
Students engage in a lesson that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the importance of...
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The Tipping Point
Students rewrite word problems and solve using math. In this word problem lesson plan, students gather data and observe the data. They relate this process to the scientific method and math. They review their data to be able to answer...
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Properties of the Centers of a Triangle
High schoolers investigate properties of the four centers of a triangle and explore a special property of the circumcenter and orthocenter of a triangle. This lesson requires the use of Cabri, Jr.
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Secant Lines; Secant Lines That Meet Inside a Circle
Young mathematicians identify different cases of intersecting secant lines. They then investigate the case where secant lines meet inside a circle.
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Can You Name That Shape?
Learners use materials to build, investigate, and draw two-dimensional shapes (polygons). They combine the shapes they have built and draw from the pile to begin a round-robin activity to name and determine the attributes of a selection...
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Algebra/Geometry Institute: Area of Polygons
Students find the area of polygons. In this area of polygons lesson, students find the area of parallelograms, rectangles, squares, and other polygons. They identify each given figure and determine the appropriate formula...
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Making Parallel Lines
Students differentiate between parallel and perpendicular lines. In this geometry lesson, students make conjectures and apply it to solve real life situations. They collect data and make predictions based on the data.
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Tessellations
Students create tessellations. In this geometry instructional activity, students use polygons to create different patterns by rotation. They identify the reasons for polygons to create the type of tessellation it does.
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Obtuse Triangles
Fourth graders explore obtuse triangles. In this geometry instructional activity, 4th graders make obtuse triangles with paper and scissors. They determine how to find the center of their triangle.
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Equilateral Triangles
Students examine the attribute of equilateral triangles. In this equilateral triangle lesson plan, 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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Exploring the Properties of Rectangular Prisms.
Students define properties of rectangular prisms. In this geometry lesson, students identify the relationship between two and three dimensional objects. They use Cabri technology to graph their figures.
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Exploring Properties of Rectangular Prisms
Learners explore the properties of rectangular prisms. In this geometry lesson, students identify properties of two and three dimensional shapes. They use Cabri technology to create polygons and solve problems.
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Tiling the Plane
Fifth graders use pattern blocks and triagular grid paper to reivew shape names, be introduced to the concept of a tiling of the plane, and determine which pattern blocks tile the plane. They are asked if they comprehend what a...