Curated OER
Angle Comparison to Right Angles
In this angles activity, students solve 4 problems in which an angle is analyzed and measured. Students tell if each angle is greater than, less than or equal to a right angle.
Curated OER
Measure Angles: Greater Less Than or Equal To?
In this measuring angles worksheet, students determine whether given angles or more than, less than or equal to 90 degrees. 
Curated OER
Easy Worksheet: Right Triangles and Circles
For this right triangles and circles worksheet, students solve 4 short answer problems. Students describe a right triangle formed by point on a circle and an angle measure.
Curated OER
Mixed Right Triangles
In this geometry learning exercise, 10th graders use right triangle trigonometry to find the missing angle measure or side length in right triangles. The one page interactive learning exercise contains ten questions. Answers and hints...
Curated OER
Measuring Angles
In this measuring angles worksheet, students solve 10 problems in which angles are measured with a protractor and labeled with: acute, obtuse, right.
EngageNY
Inscribed Angle Theorem and Its Applications
Inscribed angles are central to the instructional activity. Young mathematicians build upon concepts learned in the previous instructional activity and formalize the Inscribed Angle Theorem relating inscribed and central angles. The...
EngageNY
Secant Angle Theorem, Exterior Case
It doesn't matter whether secant lines intersect inside or outside the circle, right? Scholars extend concepts from the previous instructional activity to investigate angles created by secant lines that intersect at a point exterior to...
Scholastic
Study Jams! Area of a Triangle
Even though there is a wide variety of different triangles in the world, knowing a single equation allows us to find the area of each and every one of them. Follow along with this step-by-step presentation as Zoe clearly models how to...
Curated OER
Investigation - Adrienne's Pattern Block Angles
Fifth graders investigate possible solutions to a word problem. They explore properties of polygons and right angles. Students demonstrate proper angle measurement. Students discover patterns.
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
You Can't Go Wrong with a Right Triangle 2
Upper graders use the properties of right angle trignonmetry to measure objects such as the school flagpole. They solve real world problems using these properties.
Curated OER
Trigonometry
For this geometry worksheet, 10th graders solve problems that are based on the right triangle trigonometry and the special right triangles. The three page worksheet contains twelve questions. Answers are not included.Â
Curated OER
Geometry Chapter 7 Practice Test
In this geometry worksheet, 10th graders review problems that review a variety to topics relating to right triangles, including, but not limited to the Pythagorean Theorem, simplifying radicals, special right triangles, and right...
Curated OER
Sample Lesson Plan on Lines and Angles
Student complete worksheet using the definitions of lines and angle vocabulary. They define the word and follow a direction given on the worksheet such "construct a line." They complete an online tutorial on how to measure angles using a...
EngageNY
Angle Sum of a Triangle
Prove the Angle Sum Theorem of a triangle using parallel line and transversal angle relationships. Pupils create a triangle from parallel lines and transversals. They find angle measures to show that the angles of a triangle must total...
DK Publishing
Using a Protractor
Learn how to measure acute, right, and obtuse angles with a protractor. After reviewing the way the protractor works, fourth graders measure nine angles on their own. For extra practice, have them measure different angles in their...
Curated OER
Classification of Triangle Measurement & Perimeter
In this classification of triangles worksheet, 10th graders identify and complete 8 different problems that include determining the measurement and perimeter of various types of triangles. First, they color all right, acute, and obtuse...
Curated OER
Angle Relationships
Over the course of 18 problems, learners identify angles as complementary, supplementary, vertical or adjacent. They name relationships in angles such as alternate interior, corresponding, and alternate exterior angles. They apply the...
EngageNY
More on the Angles of a Triangle
Angles and triangles: they're all connected. Uncover the connections between angles in triangles. Scholars learn how to find both exterior and interior angle measures in triangles. The lesson emphasizes the vocabulary related to these...
CK-12 Foundation
Angle Classification: Crazy Quilt
There's more to a quilt than just a pretty pattern—there's geometry! Explore angle classification using an artistic approach to show your class that quilt designs are really just intricate geometric patterns. Here, scholars create a...
Curated OER
Tell Me! Geometry
In this geometry and measurement worksheet, students solve 20 problems pertaining to parallel lines, geometric figures, right angles and simple measurements.
Curated OER
Special Right Triangles
In this special right triangle worksheet, students use the trigonometric functions to determine angle measurement or the length of one side of a right triangle. This one-page worksheet contains 18 problems. Answers are provided at the...
Curated OER
Angles Measure and Classify
In this angles worksheet, students solve 6 problems in which an angle is measured with a protractor. Students mark if the angle is acute, right, obtuse or straight.
Curated OER
Measuring Angles
Middle schoolers explore angle measure as they estimate angle measure and measure and draw angles of less than 360 degrees. The activity emphasizes the use of estimation when measuring angles.