Willow Tree
Three-Dimensional Figures
Time to move into the third dimension! Learn the names of the geometric solids and count faces, edges, and vertices. Then learn to recognize nets that create a given solid.
Curated OER
Triangle Congruence with Coordinate
Two triangles are displayed on a coordinate plane. Youngsters apply a reflection and a translation to demonstrate their congruence. This exercise makes a terrific tool for teaching these concepts, or a way to assess learning.
K-5 Math Teaching Resources
2-D Shape Cards
Add some visual support to your elementary geometry lessons with this set of printable shape cards. From triangles and squares to octagons and nanogons, this simple resource can be used in countless ways to develop children's knowledge...
Curated OER
Exploring the Circumcenter of a Triangle
Students construct the circumcenter of a triangle. In this constructing the circumcenter of a triangle lesson, students construct a triangle using Cabri Jr. Students draw perpendicular bisectors of the sides of the triangle. Students...
Curated OER
Triangle Inequality Theorem
High schoolers investigate the relationship between angle measures and sides of a triangle and the relationships among the three sides of a triangle. The use of technology (Cabri, Jr.) allows learners to make and test conjectures as they...
Mt. San Antonio Collage
Inequalities in a Triangle
Stuck with triangle proofs? Take a 180° and provide learners with a guided worksheet that tests their knowledge with triangle inequalities. The questions require different types of proofs that range in levels of difficulty.
Curated OER
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.
Curated OER
Triangles
In this triangles worksheet, 10th graders solve and complete 22 different problems related to various types of triangles. First, they name the shortest and longest sides and the smallest and largest angles in each of triangles...
Curated OER
Easy Worksheet: Classify the Triangle
In this classify the triangle worksheet, students solve 6 short answer problems. Students identify the type of triangle being described according to its angle measures and side lengths.
Curated OER
Three-dimensional Shapes
In this three-dimensional shapes worksheet, 6th graders identify and complete 4 different questions that include various types of three-dimensional shapes. First, they identify the shape illustrated as it relates to a cube. Then,...
Curated OER
Special Right Triangles
Using the Pythagorean Theorem to solve for missing angles, young scholars evaluate right triangles and their properties.
Concord Consortium
Circling Trains
And round and round the park we go! Given a description of an amusement park with the locations of three attractions connected by walkways, learners consider what happens when additional attractions join the mix by doubling the length of...
Centers for Disease Control and Prevention
Understanding the Epidemiologic Triangle through Infectious Disease
Introduce infectious diseases and the epidemiologic triangle. A helpful resource describes the agent, host, and environment from the three vertices as well as the time factor, which is in the middle. Scholars complete a simple...
Curated OER
Understand Categories of Shapes
This colorful set of shapes and figures is the data set learners need to fill out an extensive table. For each of 11 types of shapes or figures they record the quantity and how many corners and sides each has. This becomes more difficult...
Curated OER
Congruent Triangles Postulates
Students discover three lettered postulates that prove triangles congruent.
Curated OER
Drawing a Triangle with Cabri Junior
Learners draw triangles on their graphing calculators using the Cabri Junior application. In this graphing calculator lesson, students follow step by step directions to create triangles on their calculator. They identify the type of...
Mt. San Antonio Collage
Congruent Triangles Applications
Triangles are all about threes, and practicing proving postulates is a great way to get started. The first page of the worksheet provides a brief introduction of the different properties and postulates. The remaining pages contain...
Curated OER
Patterns in Pascal's Triangle
Young scholars examine the patterns in Pascal's Triangle. In this recognizing lesson, students view a model of Pascal's Triangle and describe the patterns of the multiples. Young scholars identify the shapes that are made within Pascal's...
Mathed Up!
Pythagoras' Theorem
Use a right method to find a distance. Given a right triangle, class members find the length of one side given the measurement of the other two sides—the missing side may or may not be the hypotenuse. A video reminds the pupils how to...
Houghton Mifflin Harcourt
Unit 3 Math Vocabulary Cards (Grade 1)
Reinforce math vocabulary with a set of flashcards. Each card showcases a boldly typed word or a picture representation with labels. The topics are geometry related and include terms such as cones, faces, pyramids, sides, and more!
Curated OER
Travel Triangles
Students demonstrate and understanding of the three types of angles using triangles and quadrilaterals. In this angles lesson plan, students learn about acute, obtuse and right angles. They use cut-outs to find the areas of triangles and...
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts to finding...
Curated OER
Triangles
In this triangles learning exercise, 10th graders solve 3 extensive informal geometry problems that involve triangles. First, they sketch a triangle, selecting 3 of the sides and constructing 3 midpoints. Students then draw each of 3...
Curated OER
Triangles
Students identify triangles in the real world and construct their own triangle using drinking straws. They explore abstract triangles and find additional geometric shapes such as trapezoids. Students discuss similar shapes and examine...