Illustrative Mathematics
Lines of Symmetry for Triangles
What can symmetry tell us about triangles? After looking at four examples, learners will come to realize that lines of symmetry are different for equilateral, isosceles, and scalene triangles. Use this guided practice activity as an...
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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,...
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Identifying a Triangle by its Sides and Angles
Identify triangles by their angle measures and side lengths by looking at and measuring angle measures and side lengths. Use Cabri Jr. to construct various triangles, then manipulate the construction to create the 6 types of triangles,...
Curated OER
SuperShapes, Part 1; "Tri"ing Triangles
An outstanding lesson on triangles awaits your math scholars. Learners focus on the triangle, which is the strongest of all polygons. They see the role that triangles play in the design of buildings, and learn about triangle...
Curated OER
Geometric Figures-Triangles
Fourth graders explore triangles. For this math lesson, 4th graders discuss the different types of triangles. Students create triangles using wiki sticks. Students complete an online matching game.
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Exploring Triangles
Students research the different types of triangles, including right, isosceles, scalene, and equilateral triangles. They identify the characteristics of various types of triangles and then draw them using appropriate vocabulary to...
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Triangle Congruence with Rigid Motion
Combine transformations and triangle congruence in a single lesson. Scholars learn to view congruent triangles as a rigid transformation. Using triangle congruence criteria, learners identify congruent triangles and the rigid...
Curated OER
Triangle Puzzler
In this math worksheet, students analyze a chart and identify the names of 9 types of triangles. Students also find as many kinds of triangles they can in a given figure.
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Pascal's Triangle
Students explore the concept of Pascal's Triangle. In this Pascal's Triangle lesson, students use an applet called 'Coloring Multiples' to explore Pascal's Triangle. Students develop patterns starting with various numbers in Pascal's...
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
Patterns in Pascal's Triangle
Students 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. Students identify the shapes that are made within Pascal's Triangle.
Curated OER
Special Right Triangles
Using the Pythagorean Theorem to solve for missing angles, students evaluate right triangles and their properties.
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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...
Curated OER
Types of Triangles
Fifth graders explore the required functions of the Geometer's Sketchpad. Using the computer software, they construct similar triangles and identify them by angles and sides. Students classify triangles. Afterward, they complete problems...
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...
Curated OER
Types of Triangles
Students classify triangles by the length of their sides. In this geometry lesson, students use a white board to demonstrate the angles of various triangles. Students construct an equilateral, isosceles, and a scalene triangle.
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Classifying Triangles by the Length of the Sides Using Cabri Jr.
Learners follow detailed directions to create triangles on their graphing calculator. In this properties of triangles lesson, they will create triangles on their calculators using the Cabri Jr. application. They then identify three...
Curated OER
Basic Right Triangles
Elementary schoolers examine the attributes of triangles. In this triangle lesson plan, learners compare regular triangles and right triangles. They explore vertices and angles and investigate obtuse and acute angles. Pupils draw...
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Identify triangles
Students explore triangles. In this geometry instructional activity, students will create note cards with pictorial depictions of right, acute,obtuse, scalene, isosceles, equilateral and equiangular triangles. Students will verbally...
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Exterior and Interior Angles of Triangles
Tenth graders explore the exterior and interior angles of triangles. They use a theorem in order to prove a theorem about all polygons. Students use the theorem and its applications to find the angles of different types of triangles.
Curated OER
The Truth About Triangles And Proofs
Learners 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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Transforming Triangles
Sixth graders graph translations (slides) and reflections (flips) on a coordinate plane. They visualize and identify geometric shapes after applying transformations on a coordinate plane. Finally, 6th graders write a paragraph telling...
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Shape Up
Learners explore differents types of triangles and quadriaterals. In this polygon lesson, students model identify and compare two and three dimensional geometric figures. Learners create tangrams and discover the difference between...
Curated OER
Guess My Shape
Learners play a game with shapes. They work in groups to identify the names and characteristics of various shapes. They give each other clues to see if others can identify the shape being described. This is a great hands on activity.