Curated OER
Elastic Band Shapes
Students identify basic shapes (triangle, square, rectangle, circle), create shapes with different body parts, and create shapes at various levels (high, low)
Government of Alberta
Learn Alberta: Math Interactives: Exploring and Solving Triangles
This multimedia Learn Alberta math resource focuses on the many triangles that are found in our everyday environment. The accompanying interactive component asks students to find triangles in a picture and to solve for the missing angles...
PBS
Pbs Learning Media: Triangles
In this video segment [2:01] from Cyberchase, the CyberSquad finds that by arranging triangle tiles they are able to create a path that will allow them to cross a river of hot lava.
Shodor Education Foundation
Shodor Interactivate: Lesson: Pythagorean Theorem
Use triangles and worksheets to guide the learning of triangles to the discovery of the Pythagorean Theorem.
Science Buddies
Science Buddies: Gigantic Triangles: Measuring Altitude (Inclinometer)
If you've ever wondered how tall that bridge is, or how high your kite was, then this could be a good project for you. You'll learn how you can use the mathematics of right triangles to measure the height of an object with two...
Beacon Learning Center
Beacon Learning Center: Anglemania!
Students explore four types of angles in this interactive web lesson.
Beacon Learning Center
Beacon Learning Center: Triangles Side by Side
This comprehensive web lesson describes how to classify triangles by their angle and side measurements. It provides real-world examples and exercises for students to practice the skill.
Maths Challenge
Maths challenge.net: Triangle Area
Find the area of this triangle in a coordinate plane.
University of Saskatchewan (Canada)
University of Saskatchewan: Geometry
The University of Saskatchewan's Department of Mathematics and Statistics provides high school students with online tutorials and exercises on what they deem some of the most important topics in geometry: Triangles, and Circles and Other...
University of Saskatchewan (Canada)
University of Saskatchewan: Advanced Trig Exercises
Site provides five example problems dealing with real life trigonometry applications. Hints and solution links are provided.
Harvard University
Harvard Smithsonian: Everyday Classroom Tools
The focus of this series of lessons is to engage students in an exploration of the world around them. The emphasis is on inquiry as students learn about the earth, sun, light, shapes and more.
Maths Challenge
Maths challenge.net: Measuring Mountains
Use your triangle solving skills to solve this triangle problem and then apply it to the real world.
McGraw Hill
Glencoe: Self Check Quizzes 2 Triangles
Use Glencoe's Math Course 2 randomly generated self-checking quiz to test your knowledge of a variety of triangle topics. Each question has a "Hint" link to help. Choose the correct answer for each problem. At the bottom of the page...
National Council of Teachers of Mathematics
Nctm: Illuminations: Tube Viewer Simulation
A computer simulation of viewing through various lengths of tubes at different distances. The simulation also has an exploration of focus questions. [Requires Java.]
TeachEngineering
Teach Engineering: Stay in Shape
In this activity, students will learn that math is important in navigation and engineering. Ancient land and sea navigators started with the most basic of navigation equations (Speed x Time = Distance). Today, navigational satellites use...
That Quiz
That Quiz: Practice Test: Triangles
Test your knowledge on the attributes of triangles. There are eleven levels that may be completed with or without a timer.
University of Georgia
University of Georgia: An Elementary Application of Similar Triangles
Excellent review site on similar triangles. Includes diagrams and explanation of application.
Wolfram Research
Wolfram Math World: Triangles
This site provides detailed overviews of many of the concepts and theorems associated with triangles. Content focuses on general triangles, cevians, triangle centers, triangle circles, and triangle lines.
National Council of Teachers of Mathematics
The Math Forum: Triangle Formulas
Investigate the geometric definitions of triangles, focusing upon equilateral, isosceles, right, and scalene with detailed drawings and appropriate formulas for each. This site has links to more information on triangles.
Oswego City School District
Regents Exam Prep Center: Angles and Triangles
On this site a viewer can learn about the different types of triangles, and categorized by either angles or sides. Tutorials are also included for interior and exterior angles of triangles. A teacher resource page includes a lesson plan...
Oswego City School District
Regents Exam Prep Center: Mid Segment of a Triangle
Three resources to help you plan instruction on the mid-segment of a triangle: a lesson with definition, properties, and examples of a mid-segment of a triangle; a seven-question quiz through which students can practice working with...
Shodor Education Foundation
Shodor Interactivate: Triangle Explorer
This applet allows users to study the nature of triangles and their area. It draws random triangles on a Cartesian coordinate system. The user can determine the area of the triangle using his or her preferred method. After the calculated...
Mathigon
Mathigon: Geometry: Polygons and Polyhedra: Polygons
This lesson focuses on polygons; a polygon is a closed, flat shape that has only straight sides. Polygons can have any number of sides and angles, but the sides cannot be curved.
University of Georgia
University of Georgia: Inter Math: Recommended Investigations of the Triangle
Investigate the qualities of a triangle with these seventeen word problems. Many include ways to extend the lesson.