Curated OER
Angles: Greater Than, Less Than or Equal To 90 Degrees?
In this angles worksheet, students check the correct box, identifying angles as either greater than, less than or equal to 90 degrees. A reference web site is given for additional activities.
Utah Education Network (UEN)
The Angle Tangle
Fourth and fifth graders identify three types of angles, recognize that angles are measured in degrees, measure angles using protractors or angle rulers. They classify angles as a class, classify angles on pattern blocks, and complete a...
Curated OER
Observing Root Response After Rotating Plant Ninety Degrees
Students conduct an experiment to observe the response of maize roots when rotated 90 degrees.
Curated OER
Drawing Angles
Get out those protractors! Once geometers can identify obtuse, acute, right, and straight angles, get them to measure and draw their own. There are six boxes here, each with an angle measurement. Learners use a protractor to draw the...
Chapman University
Graphs of the Sine and Cosine Function in Degrees
This bright, clear, graphic, display of the sin(x) and cos(x) functions spans the domain between -360 degrees and 360 degree. Use it as a poster, handout, presentation slide, or project it onto a whiteboard.
CK-12 Foundation
Relationships of Sides in 30-60-90 Right Triangles: Truck on a Mountain Road
Determine the change in elevation on a mountain road. Individuals use the interactive to simulate a truck driving up a mountain road with a 30-degree incline. They determine missing sides of a 30-60 right triangle to find horizontal and...
Institute of Electrical and Electronics Engineers
Conveyor Engineering
Moving along the line. Class members research how a conveyor belt works in order to gain background information. Groups then design a conveyor belt that will carry a piece of candy four feet and along a 90-degree turn. The groups build...
Curated OER
Reflection of Light
Students experiment with reflections of two plane mirrors placed at a 90 degree angle to see what will be reflected.
EngageNY
Definition of Rotation and Basic Properties
Examine the process of rotating images to visualize effects of changes to them. The fifth lesson plan of 18 prompts pupils to rotate different images to various degrees of rotation. It pays special attention to rotations in multiples of...
EngageNY
Designing a Search Robot to Find a Beacon
Build right angles using coordinate geometry! Pupils explore the concept of slope related to perpendicular lines by examining 90-degree rotations of right triangles. Learners determine the slope of the hypotenuse becomes the opposite...
DiscoverE
Conveyor Belt
Convey your interest in conveyor belts. By considering different size tubes, groups create a conveyor belt that can transport boxes of candy at least four feet. Also, the conveyor belt must make a 90-degree turn—quite a difficult task!
Curated OER
Angles
Fourth and fifth graders investigate angles and name them according to the criteria for obtuse, acute, and right angles. They examine a human-made yarn pattern on the floor of their classroom and identify angles, vertices, and types of...
Curated OER
Angles-Greater Than, Less Than or Equal To 90 Degrees?
For this angles worksheet, students determine whether given angles are greater than, less than or equal to 90 degrees, checking the appropriate answer. A reference web site is given for additional activities.
Illustrative Mathematics
Are These Right?
Is that a right triangle or a wrong triangle? Young mathematicians look at eleven different shapes and use a measuring tool of their choice to determine which triangles have right angles. Consider cutting out sets of the shapes to...
CK-12 Foundation
Latitude, Longitude, and Direction: Angle from the Equator
Which has the higher IQ, latitude or longitude? Longitude because it has 360 degrees! The interactive introduces the way latitude is measured and why it can never have more than 90 degrees. A handful of challenge questions encourage...
Curated OER
Square Corners
Which ones are square corners? As they learn more about shape attributes, be sure scholars understand the difference between a vertex and a square corner. After examining two examples, learners circle the 90-degree corners in 12...
Illustrative Mathematics
Finding an Unknown Angle
Teach your class how to apply their knowledge of geometry as they explore the unknown. In order to find an unknown angle, students must understand that rectangles have four interior right angles, that right angles have 90 degrees, and...
West Contra Costa Unified School District
Dilations Using Right Triangles
Don't argue with a triangle that has a 90-degree angle. It's always right. Scholars first use right triangles to help draw dilations of points. They continue the lesson by applying this skill to draw dilations of polygons.
CK-12 Foundation
Proofs: Angle Pairs and Segments—The Three Angle Problem
Finding the sum of the measures of three angles is easy, unless you have no clue what the measures are. Learners use an interactive diagram to see a geometric problem in a different way. A set of challenge questions takes them through...
Flipped Math
Rotations
Turn the class around. Scholars define rotations of multiples of 90 degrees and create algebraic mappings for them. After an introduction to symmetry, pupils determine which letters of the alphabet have rotational and reflectional...
Virginia Department of Education
Rotation
Rotate this resource into your lesson plans. Scholars rotate polygons in the coordinate plane by multiples of 90 degrees. They then compare the original and new figures to develop conjectures about coordinate points after rotations.
Embedded Math
The Unit Circle
You and your learners will enjoy having a nicely organized, typed up unit circle, all filled in with degrees and radians as well as cartesian coordinates.
Curated OER
Geometry - Angles Overview
Learners address 14 questions that include naming all pairs of opposite and supplementary angles for sets of intersecting lines and then, finding the measure of the unknown angle. They determine the measure of the angle that is...
EngageNY
Sine and Cosine of Complementary Angles and Special Angles
Building trigonometric basics here will last a mathematical lifetime. Learners expand on the previous lesson in a 36-part series by examining relationships between the sine and cosine of complementary angles. They also review the ratios...