Curated OER
Triangle Similarity
In this triangle similarity activity, 10th graders solve and complete 12 different problems that include defining similar and 3 similar statements using only sides and angles. First, they determine if each pair of triangles shown are...
Curated OER
Triangle Classificaition with Geometer's Sketchpad.
Learners use Geometer's Sketchpad to draw triangles and explore the classificaiton of each using the mearsures of interior angles and the lengths of the sides.
Curated OER
The Sum of All Angles
Young scholars add up the different angles using the angle addition postulate. In this geometry instructional activity, students differentiate between interior and exterior angles. They calculate the different angles for triangles and...
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...
Beacon Learning Center
Angles and Algebra
Middle schoolers calculate angle measure for triangles and complementary/supplementary angles. After a lecture/demo, students utilize a worksheet imbedded in this plan to gain practice.
Curated OER
Proofs
In this geometric proof learning exercise, 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...
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...
Houghton Mifflin Harcourt
Developing the Concept: Triangles and Quadrilaterals
Exact narrative and examples make this lesson on polygons easy to implement. Through it, your class will learn how to use a protractor and ruler to construct triangles and quadrilaterals according to your directions. Your class will be...
Houghton Mifflin Harcourt
Introducing the Concept: Triangles and Quadrilaterals
Guide your geometers through the process of constructing polygons. They learn how to draw triangles, squares, parallelograms, rectangles, rhombuses, and trapezoids with specified angles using a protractor and a ruler. The lesson plan...
Curated OER
Patterns in the Sums of Polygon Angles
Sixth graders discover the patterns of sums of polygon angles. In this math lesson plan, 6th graders study the properties of geometric shapes to solve problems as they participate in hands-on activities.
Curated OER
Geometric Figure Quiz
In this geometric figure worksheet, students answer 10 multiple choice questions about geometric figures. Students find missing angles, interior angles, properties of polygons, etc.
Curated OER
Triangle Sum Theorem
Tenth graders investigate the theorems of angles and lines to prove triagle sum theorem. 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...
Key Curriculum Press
Triangle Inequalities
Properties about triangles are explored in this instructional activity. Geometers make conjectures about the length of a triangle's sides, the length of the angles in relation to the length of the sides, and the measure of the exterior...
Curated OER
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.
Curated OER
Triangles
In this geometry activity, 10th graders solve problems involving triangular inequality. They apply the proofs and theorem of triangles to solve these problems. There is an overview and one question.
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
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
Pythagorean Theorem
Seventh graders practice calculations using the Pythagorean Theorem to find the missing side of a right triangle. Through guided practice, 7th graders explore how to apply the Pythagorean Theorem to solve for a missing variable. ...
Curated OER
Tessellation Trial and Error
In this interactive lesson, students 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
Connecting Formulas Related to Geometric Figures
Students identify diagrams of quadrilaterals and circles by different names and classify the figures. They name the areas for each diagram and practice solving the formulas for each.
Virginia Department of Education
High School Mathematics Geometry Vocabulary Word Wall Cards
Having a good working knowledge of math vocabulary is especially important for geometry learners. Here are 119 pages worth of wonderfully constructed definitions, constructions, formulas, properties, theorems, and postulates. This is a...
Mt. San Antonio Collage
The Trapezoid
Enjoy this nicely organized worksheet that puts together multiple problems regarding trapezoid proofs. The resource can be used as a guide that begins with proving properties and ends with solving for measures of line segments.
Curated OER
CORNER CABINET
Ninth and tenth graders calculate the length, width, height, perimeter, area, volume, surface area, angle measures or sums of angle measures of common geometric figures. They solve problems involving scale drawings, models, maps or...
Curated OER
T Points from Directions
Here is a instructional activity that starts with having geometers translate points using compass directions into an accurate picture of the problem. Then they must use their knowledge of the Pythagorean theorem or similar triangles to...