Scholastic
Study Jams! Classify Triangles
Jam on with this multi-faceted activity teaching triangle classification. Start with a learner-paced lesson describing the different qualities of triangles and follow with a fun karaoke session. Also provided are two types of...
Curated OER
Classify Triangles
Here is a classifying triangles practice activity in which learners sharpen their problem solving skills as they solve six story problems.
National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this activity series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy...
Curated OER
Toothpick Triangles
Students draw a chart (included in the lesson) to use with their investigation. They review terminology of triangles and receive toothpicks to use in the lesson. Beginning with three toothpicks, students form a triangle. They complete...
Digging Into Math
Classifying Triangles
Young mathematicians explore the world of three-sided shapes in this lesson on the different types of triangles. Starting with a general introduction to classification using Venn diagrams, children learn how to categorize triangles based...
Curated OER
Acute Triangles
Learners study acute triangles. They measure angles using a protractor, then classify the triangles as either right, obtuse, or acute. Everyone creates a design for a Navajo rug using only acute triangles.
Curated OER
Classifying Triangles
In this classifying triangles instructional activity, 6th graders write the type of triangle, acute, right or obtuse, for 9 pictures of triangles, answers included.
Curated OER
Classifying Triangles
This presentation shows how triangles are classified by angle measurement and length of sides. It reviews isosceles, scalene, obtuse, right, and acute classifications and includes questions for students to classify some of the triangles...
K-5 Math Teaching Resources
Triangle Pack
With so many different types of triangles, it can be a challenge for young mathematicians to keep them all straight. Luckily this set of printable triangles is here to engage children in comparing and sorting triangles by their...
Curated OER
SuperShapes, Part 1; "Tri"ing Triangles
An outstanding instructional activity 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...
McGraw Hill
Triangles
After reviewing characteristics of seven types of triangles, young geometers discover how to find the missing angle of a triangle. Then, they practice identifying triangles, find missing angles, and find missing side lengths of similar...
Virginia Department of Education
Classifying Angles
Don't be obtuse, this geometry unit is the just the right resource for educating the acute young minds in your class. From classifying and measuring angles, to determining the congruence of shapes, this resource covers a wide range of...
Curated OER
Triangle Designs
In this triangles learning exercise, students draw different triangles and write how many sides and angles each one has. Students draw 4 kinds of triangles and have 2 that are impossible to draw.
University of Exeter
Angles and Turns
Junior geometers investigate the concepts of angles and turns using straws to perform a hands on activity. This is helpful for kinesthetic learners who have a hard time with mathematics. The lesson includes the dialogue to be used during...
Curated OER
Right Triangles
Learners classify triangles and make connections regarding angle measurements and attributes of acute, right, and obtuse triangles. They listen to teacher define and explain triangles. Everyone imagines a place where a broken wing for a...
Curated OER
The Greedy Triangle-Intro to Geometric Shapes
In this geometry lesson, learners read The Greedy Triangle and use geoboards to construct geometric shapes. They identify the number of sides and angles each shape has.
Curated OER
Constructions and Angles
In this triangle constructing and classifying worksheet, students read through a tutorial on triangles and angles. Then, students complete 17 exercises in which they answer questions about angles and triangles. By clicking on the "Check"...
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
Angles, Triangles, Quadrilaterals, Circles and Related
Students classify angles. In this angles lesson, students explore the characteristics of angles, triangles, quadrilaterals and circles. They identify polygons and sing a classifying angles song. Students participate in a manipulative...
Math Mammoth
Triangles 1
In this triangles worksheet, learners measure and calculate the measurements of eight triangles, their sums and classify the triangles as acute, obtuse or right.
Math Mammoth
Classify The Triangles
In this math worksheet, students measure all the angles in these triangles. They also calculate the sum of the angles and classify the triangles.
Curated OER
Geometric Shapes
Students identify polygons. In this geometric shape lesson, students explore the characteristics of polygons. They identify polygons, and classify triangles according to their sides and angles. Students create a poster representing...
PBS
Accessible Shapes
All the 2-D and 3-D measurement work you need is in one location. Divided into three sections, the geometry lesson plans consist of visualization of three dimensions, classifying geometric figures, and finding surface area and volume....
Curated OER
Nets And Surface Area
Upper graders investigate how to find the surface area when using two-dimensional shapes. They conduct an investigation in groups while working sample problems given during class discussion with the teacher. They also review how to...