Maths Challenge
Maths challenge.net: Right Triangle Equal Parts
A geometry proof problem involving a right triangle and finding angles of equal measure.
Quia
Quia: Introduction to Angles
Use this website to practice angle definitions using a matching game format.
Quia
Quia: Introduction to Angles Flashcards
Use this website to practice angle definitions using a flash card format.
Quia
Quia: Introduction to Angles Concentration
Use this website to practice angle definitions using a concentration game format.
Quia
Quia: Introduction to Angles: Word Search
Use this website to practice angle definitions using a word search format.
CK-12 Foundation
Ck 12: Determination of Unknown Triangle Measures Given Area
[Free Registration/Login may be required to access all resource tools.] Looks at triangle problems where you are given the area and must use trigonometry to find unknown sides or angles.
Khan Academy
Khan Academy: Angular Measure 2
Looking for an easier way to do angular measurements? This page introduces you to a trick by using skinny triangles with small angles. The skinny triangles lets the astronomer assume right triangles and then they can use trigonometry to...
Shodor Education Foundation
Shodor Interactivate: Lesson: Perimeter (Elementary)
In this lesson students will practice finding the perimeter of regular and irregular shapes with right angles and the appropriate units for measuring perimeter.
Shodor Education Foundation
Shodor Interactivate: Lesson: Area (Elementary)
In this lesson students will practice finding the area rectangular shapes and irregular shapes with right angles and understand why the area formula works for rectangular shapes.
Homeschool Math
Homeschool Math: Triangles
This lesson plan provides students with an opportunity to practice drawing and measuring triangles and angles. It also shows pictures and gives definitions of each type of angle and triangle.
Exploratorium
Exploratorium: Ilion High: Build a Clinometer
Instructions for building a clinometer are given on this page. Clinometers can be used to measure the angle of elevation of a right triangle, and in turn find the height of large objects.
Clark University
Clark University: Dave's Short Trig Course: Tangents and Slopes
Explains what "tangent" is and its role in the right triangle. Slope of a line is investigated and tangent for special common angles is given. Angle of elevation and angle of depression are also covered here.
Texas Instruments
Texas Instruments: Looking for Mr. Right Triangle
Navigator Activity: This is a review of the right triangle in the coordinate plane. Given two lines (2 really nice ones) the students write the equation of the 3rd line to create a right triangle. They find the vertices of the triangle...
TeachEngineering
Teach Engineering: Trigonometry via Mobile Device
Students investigate the relationships between angles and side lengths in right triangles with the help of materials found in the classroom and a mobile device.
TeachEngineering
Teach Engineering: Handheld Trigonometry
In addition to understanding the concept of similar right triangles and how they apply to trigonometric ratios, students explore a clinometer app, and discover how it can be used to test the mathematics underpinning trigonometry.
TeachEngineering
Teach Engineering: You've Got Triangles!
Students learn about trigonometry, geometry and measurements while participating in a hands-on interaction with LEGO MINDSTORMS NXT technology. First they review fundamental geometrical and trigonometric concepts. Then, they estimate the...
ClassFlow
Class Flow: Angles in Geometry
[Free Registration/Login Required] This flipchart is a look at angles in geometry. Drawing, labeling, measuring, special angles: (right, straight, acute, obtuse) and congruence.
Physics Aviary
Physics Aviary: Triangle Exploration Lab
This lab is designed to have students look at some of the different relationships that exist in a right triangle. Students will be able to change the x-leg and y-leg of the triangle and then measure the angle and the hypotenuse of the...
CK-12 Foundation
Ck 12: Algebra Ii: 4.3 the Unit Circle
Activities in this lesson explore how to identify the coordinates where special right triangles intersect with the unit circle in all four quadrants, use both degrees and radians to identify angles, and explore angles of different sizes...
Shodor Education Foundation
Shodor Interactivate: Squaring the Triangle
Learn about how the Pythagorean Theorem works through investigating the standard geometric proof.
Curated OER
Zona Land: Trigonometry Right Triangles
Introduction to right triangles and how to solve them using trigonometric functions. Very nice interactive demonstration of what happens when the angle measurements change and how it effects the calculations. This visual might be just...
Curated OER
Zona Land: Trigonometry Right Triangles
Introduction to right triangles and how to solve them using trigonometric functions. Very nice interactive demonstration of what happens when the angle measurements change and how it effects the calculations. This visual might be just...
Curated OER
Zona Land: Trigonometry Right Triangles
Introduction to right triangles and how to solve them using trigonometric functions. Very nice interactive demonstration of what happens when the angle measurements change and how it effects the calculations. This visual might be just...
Curated OER
Zona Land: Trigonometry Right Triangles
Introduction to right triangles and how to solve them using trigonometric functions. Very nice interactive demonstration of what happens when the angle measurements change and how it effects the calculations. This visual might be just...