Improving Measurement and Geometry in Elementary Schools
The Sum of the Interior Angles of a Polygon
Junior geometers discover that polygons can be decomposed into triangles and that the number of triangles can be determined by a rule. Note that the Geometer’s Sketchpad® software is required to carry out all components of this lesson.
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Informal Proof of AA Criterion for Similarity
What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply...
Curated OER
Tessellation Trial and Error
In this interactive lesson, pupils review attributes of equilateral polygons. They are introduced to the concept of a tessellation. Using protractors and pre-cut shapes, students arrange a variety of tiles to create tessellations. They...
Curated OER
Congruent Triangles
For this congruent triangles worksheet, 10th graders solve and complete 10 different problems that involve various congruent triangles. First, they determine the length of the third side given the other two. Then, students determine the...
Curated OER
Triangle Inequality Theorems Investigation
Students estimate and measure triangles. In this geometry lesson, students identify the relationship between three sides and a triangle. They use the inequality theorem to decide if a triangle will be formed or not.
Curated OER
Countdown Challenge: Triangle Inequality Theorem
In this triangle inequality worksheet, students test the Triangle Inequality Theorem. They measure the sides of given triangles, identify the type of triangle, and name angles in the triangle. The one-page worksheet contains 36 problems.
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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...
Curated OER
Math Games for Skills and Concepts
A 27-page packet full of math games and activities builds on algebra, measurement, geometry, fractional, and graphing skills. Young mathematicians participate in math games collaboratively, promoting teamwork and skills practice.
Curated OER
Triangle worksheets
In this geometry worksheet, 10th graders explore triangle properties, including the sum of the measures of the angles of a triangle, the triangle inequalities, properties of isosceles triangles, properties of congruent triangles, and...
Curated OER
Polygons Multiple Choice
In this geometry worksheet, students identify the interior and exterior angles using the angle sum theorem. They identify and solve quadrilaterals using properties of quadrilaterals. There are 12 questions with an answer key.
Curated OER
Indirect Proof and Inequalities in One Triangle
In this geometry worksheet, 10th graders order the sides and angles of a triangle and determine the range of the third side of a triangle given the lengths of two sides. The one page worksheet contains sixteen questions. Answers are...
Curated OER
Geometric Concepts and Polygons
In this geometry worksheet, students identify the altitude, perpendicular bisector, median, angle bisector and the area of different polygons. There are 33 problems.
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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 Triangle,...
Curated OER
Discover the Pythagorean Theorem
Middle schoolers explore the Pythagoras theorem. In this geometry lesson, students make right triangles and identify the parts of the triangle. Middle schoolers complete measurements of the sides of the triangle.
Curated OER
Algebra and Trigonometry - Week 3: Story Problems
In this story problem activity, students read story problems, write equations, and solve. They use the law of sines, the law of cosines, the distance formula, and rates to solve problems. This two-page activity contains seven story...
Curated OER
Chapter 6: Geometry Perimeter and Area
In this perimeter and area learning exercise, students find the perimeter of various polygons. They compute the perimeter, surface area, circumference, and volume of given figures. Students explore trigonometric ratios. This...
Curated OER
Translating Transformations in Geometry
Students create an image using given coordinates and evaluate how the coordinates change when a slide or rotation takes place.
Curated OER
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 needed to...
CCSS Math Activities
Smarter Balanced Sample Items: High School Math – Claim 3
Communication is the key. A presentation provides 25 sample items for Claim 3, Communicating Reasoning, for the Smarter Balanced High School Math assessment. Items require pupils to answer the question and provide logical reasoning to...
Curated OER
A Rectangle in the Coordinate Plane
A quadrilateral is drawn on the coordinate plane, and eighth grade geometers find the length of each side and the diagonals by applying the Pythagorean theorem.
Curated OER
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.
Curated OER
Triangles Congruency Theorems
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In 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...
Curated OER
Chalkboard Challenge: Fifth Grade Math Review
This PowerPoint addresses fifth grade math concepts, focusing mostly on geometry. The interactive math review game is in a "Jeopardy" style format and enables students to revisit the topics in geometry such as polygons, quadrilaterals...
Curated OER
Triangle Conjectures
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson plan, 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...