CK-12 Foundation
Ck 12: Geometry: Angle Measures in Given Triangles
[Free Registration/Login may be required to access all resource tools.] Find the degree measure of an unknown angle in given triangles.
Texas Instruments
Texas Instruments: Classifying a Triangles by Their Angle Measure Using Cabri Jr
This activity uses Cabri Jr to classify triangles according to their angle measure. [Requires Adobe Reader.]
Shodor Education Foundation
Shodor Interactivate: Lesson: Angles
This upper elementary and middle school lesson plan introduces the concept of acute, obtuse and right angles. Also, as the instructional activity proceeds vertical, adjacent, alternate interior and alternate exterior angles are explored....
CK-12 Foundation
Ck 12: Geometry: Supplementary and Complementary Angle Pairs
[Free Registration/Login may be required to access all resource tools.] Use reasoning to figure out the measures of missing angle measures
E-learning for Kids
E Learning for Kids: Math: Pizza (Italian) Restaurant: Angles I
In this interactive website, students practice various math skills such as identifying different types of angles, use the degree symbol, estimate and measure angles, and construct angles.
E-learning for Kids
E Learning for Kids: Math: Rice Field: Angles
On this interactive website students practice various math skills using a real life scenario. Those skills include finding angles, drawing angles larger or smaller than a given angle, and locating right angles.
University of Cambridge
University of Cambridge: Nrich: Take the Right Angle
Sharpen your logic, time, and angle recognition skills while working on this challenge. The solution is available to double check your results. (Hint: Use the "90 degree" right angle button on the clock to check if something is a right...
BBC
Bbc: Angles
You can pick up some valuable pointers on angles and lines here. When you finish working your way through the pages you can take an on-line "Test Bite," and check your understanding.
Primary Resources
Primary Resources: Angles
A great place to find teacher resources on angles. Includes worksheets PowerPoint presentations and smartboard files.
Mangahigh
Mangahigh: Shape: Right Angle in a Semi Circle Rule
Test your knowledge of the measurement of angles in a triangle.
National Council of Teachers of Mathematics
Nctm: Figure This: What's My Angle?
Do people with big hands have larger angles between their fingers? See if you can find the answer this question when you try this math challenge on estimating and measuring angles. Discover how understanding angles and geometric shapes...
CK-12 Foundation
Ck 12: Geometry: Angle Classification Intermediate
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to classify angles based on their measure.
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...