Mathed Up!
Angles in Triangles and Quadrilaterals
This short video show viewers how to connect the sum of the angles in a triangle to other angle measurements. Pupils determine the missing measures for angles involved with triangles and quadrilaterals. Class members then must explain...
Curated OER
Special Triangles and Quadrilaterals
In this special triangles worksheet, students examine given special triangles. They determine the length of a missing side and/or the measurement of a missing angle for given triangles and quadrilaterals. Students justify...
Curated OER
Angle Sum of Triangles and Quadrilaterals
In this angle sum activity, students find missing angles of 20 triangles and quadrilaterals. Students find the missing angle in each polygon by using the total degrees of each and given angle measures.
Houghton Mifflin Harcourt
Developing the Concept: Triangles and Quadrilaterals
Exact narrative and examples make this lesson plan 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...
Curated OER
Developing Formulas for Triangles and Quadrilaterals
In this geometry worksheet, 10th graders determine the area of triangles, parallelograms, trapezoids, kites, and rhombuses. The one page worksheet contains eleven problems. Answers are included.
Mathematics Assessment Project
Evaluating Statements About Length and Area
Class members complete an assessment task by identifying whether statements about triangles and quadrilaterals are always true, sometimes true, or never true. They then participate in a sorting activity with the same objective.
Buffalo State
A Five Day Approach to Using Technology and Manipulatives to Explore Area and Perimeter
Young mathematicians build an understanding of area and perimeter with their own two hands in a series of interactive geometry lessons. Through the use of different math manipulatives, children investigate the properties of...
Curated OER
Triangles and Quadrilaterals
In this triangles and quadrilaterals learning exercise, 10th graders solve 6 different problems related to using triangles and quadrilaterals in informal geometry. They determine how many lines of symmetry an equilateral triangle and an...
Noyce Foundation
Lyle's Triangles
Try five problems on triangles. Levels A and B focus on shapes that can be created from right triangles. Level C touches upon the relationship between the area of a six-pointed star and the area of each triangle of which it is composed....
Curated OER
Triangles and Quadrilaterals
Second graders explore triangles and quadrilaterals. They rotate to various centers in the room to identify and examine triangles and quadrilaterals. After presenting a picture to the class, 2nd graders locate right angles, triangles...
Curated OER
Let's Explore the World of Triangles and Quadrilaterals!
Second graders explore the features of triangles and quadrilaterals. In this lesson on triangles and quadrilaterals, 2nd graders rotate with their group to five different activities all exploring a different aspect of geometry.
Curated OER
8th Grade Math Classifying Triangles and Quadrilaterals
Eighth graders engage in a lesson that is about classifying polygons with the focus being upon specific triangles and quadrilaterals. They conduct activities using cutouts for kinesthetic learners to help make connections while...
Curated OER
Family Activity: Triangles and Quadrilaterals
In this triangles and quadrilaterals worksheet, students solve 7 short answer problems. Students find objects around the house that are constructed from triangles, parallelograms, trapezoids, squares, rectangles. Students sketch the...
Illustrative Mathematics
Right Triangles Inscribed in Circles II
So many times the characteristics of triangles are presented as a vocabulary-type of lesson, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...
Illustrative Mathematics
Extensions, Bisections and Dissections in a Rectangle
Gaining practice in translating a verbal description into a diagram and then an equation is the real point of this similar triangles exercise. Once the diagram is drawn, multiple methods are provided to reach the conclusion. An effective...
Mathematics Vision Project
Congruence, Construction and Proof
Learn about constructing figures, proofs, and transformations. The seventh unit in a course of nine makes the connections between geometric constructions, congruence, and proofs. Scholars learn to construct special quadrilaterals,...
Curated OER
All Around Triangles and Quadrilaterals
In this triangle/quadrilateral worksheet, students use a centimeter ruler to draw triangles and quadrilaterals with given perimeters. Answers are included on page 2.
Curated OER
Circles, Squares, Triangles and Rectangles In Our World
Here is an engaging geometry lesson which has students identify the properties of shapes and cut shapes out of magazines. They make cookies using cookie cutters in various shapes.
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
Exploring Polygons and The Greedy Triangle
Excellent lesson plan! Anne Linehane's geometry story, The Greedy Triangle, offers an opportunity to practice forming various types of polygons with your learners. Using elastic bands (or Chinese jump ropes),...
EngageNY
Perimeter and Area of Polygonal Regions in the Cartesian Plane
How many sides does that polygon have? Building directly from lesson number eight in this series, learners now find the area and perimeter of any polygon on the coordinate plane. They decompose the polygons into triangles and use Green's...
Curated OER
Area of Triangles and Parallelograms
In this area worksheet, students find the area of 21 triangles and parallelograms. Students find the area of each triangle and parallelogram given a sketch and measurements of the figure.
Curated OER
Angles, Triangles, Quadrilaterals, Circles and Related
Middle schoolers classify angles. For this angles lesson, students explore the characteristics of angles, triangles, quadrilaterals and circles. They identify polygons and sing a classifying angles song. Middle schoolers participate...
Curated OER
The Quirky Quadrilateral
Fourth graders identify and classify different triangles and quadrilaterals. Then they demonstrate an understanding of plane and solid geometric objects and use this knowledge to show relationships and solve specific problems. Students...