ClassFlow
Class Flow: Right Angles
[Free Registration/Login Required] This flipchart is designed to introduce the student to the concept of the right angle and to give the student practice in identifying right angles as well as measuring angles with a protractor.
AAA Math
Aaa Math: Types of Triangles Based on Angles
Students can practice classifying triangles based on angle measurements through a series of self-check exercises and timed learning games.
Math.com
Math.com: Building Blocks: Classifying Angles
This geometry resource investigates types of angles. Definitions, detailed examples, and practice problems are included.
ABCya
Ab Cya: Bow and Angle
Join the heroes Loxley, Arrowyn, Busido, and Mockingbird in this epic adventure of Bows and Angles! Practice measuring and reading angles while you defend yourself from treacherous shadow ninjas.
University of Cambridge
University of Cambridge: Nrich: Game Do You Measure Up?
This interactive game gives you a variety of measuring tools and measuring opportunity. For this game of chance you choose the correct tool for the job that needs to be measured. Everything you need for this game is listed and/or...
Khan Academy
Khan Academy: Solve for an Angle in Right Triangles
Given two sides in a right triangle, find one of the acute angles using trigonometry.
ClassFlow
Class Flow: Angle Measurement
[Free Registration/Login Required] This flipchart uses the protractor tool to understand the classification and naming of angles: acute, obtuse and right.
OER Commons
Oer Commons: Pre Assessment
Students solve for missing angle measures by applying what they have learned about types of angles and the angle measures of polygons. Students do a pre-assessment at the end of the lesson.
Illustrative Mathematics
Illustrative Mathematics: 4.g Are These Right?
The purpose of this task is for students to measure angles and decide whether the triangles are right or not. Aligns with 4.G.A.2.
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.
Government of Alberta
Learn Alberta: Math Interactives: Exploring Trig Ratios
Investigate the cosine, sine, and tangent ratios of trigonometry using this interactive Learn Alberta math resource. Students will use these ratios to determine a right triangle's unknown side or angle. Be sure to follow the link to the...
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...