EngageNY
Special Triangles and the Unit Circle
Calculate exact trigonometric values using the angles of special right triangles. Beginning with a review of the unit circle and trigonometric functions, class members use their knowledge of special right triangles to find the value of...
Shodor Education Foundation
Triangle Area
While the lesson plan focuses on right triangles, this activity offers a great way to practice the area of all triangles through an interactive webpage. The activity begins with the class taking a square paper and cutting in in half; can...
EngageNY
Special Relationships Within Right Triangles—Dividing into Two Similar Sub-Triangles
Why are right triangles so special? Pupils begin their study of right triangles by examining similar right triangles. Verifying through proofs, scholars recognize the three similar right triangles formed by drawing the altitude. Once...
Curated OER
A Special Relationship
Students discover the relationships of the lengths of the sides of right triangles and right triangles using a series of drawings on dot paper. They investigate and solve problems of standard (customary and metric units) and non-standard...
EngageNY
Prove the Pythagorean Theorem Using Similarity
Amaze your classes with the ability to find side lengths of triangles immediately — they'll all want to know your trick! Learners use the Pythagorean Theorem and special right triangle relationships to find missing side lengths.
Mathalicious
Been Caught Stealing
You're safe, when calculating the odds of stealing second base! Learners compare the rate of a runner to the distance the ball travels, in a lesson that explores right triangles and measurement. Full of discussion questions and fun...
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts to finding...
Willow Tree
The Pythagorean Theorem
There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...
Curated OER
Studying Special Segments in Triangles
Learners investigate special segments in triangles. In this geometry instructional activity, students graph, compare, estimate and predict findings based on their data. They differentiate between similarity and congruence of triangles.
EngageNY
Complex Numbers and Transformations
Your learners combine their knowledge of real and imaginary numbers and matrices in an activity containing thirty lessons, two assessments (mid-module and end module), and their corresponding rubrics. Centered on complex numbers and...
Curated OER
Clowning Around: Drawing
Kids create a clown out of shapes. They work to show emotions while practicing their drawing skills. Pupils use circles, triangles, squares, oil pastels, and their imagination to draw, color, and decorate a sad or happy clown. Tip: Have...
Curated OER
Investigating the Idea of Cos
Fifth graders use cos to solve problems involving right-angled triangles. They solve equations of the form cos(++) = a, for a between -180 and 360 degrees. They state the value of cos(++) in special cases and graph y = cos(++).
EngageNY
Why Call It Tangent?
Discover the relationship between tangent lines and the tangent function. Class members develop the idea of the tangent function using the unit circle. They create tables of values and explore the domain, range, and end behavior of the...
EngageNY
Copy and Bisect an Angle
More constructions! In this third installment of a 36-part series, learners watch a YouTube video on creating door trim to see how to bisect an angle. They then investigate how to copy an angle by ordering a given list of steps.
Curated OER
Geometry: Lesson 10
Eighth graders investigate the Pythagorean theorem and how it is used in geometry. Measurements for different triangles is given and then students must solve problems in order to practice using the formula.
Curated OER
Exploring Geometric Mean
Students solve problems using geometric means. In this geometry lesson, students create altitudes in right triangles. They use Cabri software to move the triangle around and observe different sides and angles.
Curated OER
Exploring Geometric Mean
Student identify the solution using geometric mean. For this geometry lesson, students create right triangles where the altitude of the triangle is the side containing the right angle. They modify shapes using Cabri software and observe...
Curated OER
Investigating the Idea of Sin
Fifth graders use sin to solve problems involving right-angled triangles, Solve equations of the form sin(++) = a, for a between -180++ and 360++. They State and graph the value of sin(++) in special cases. They describe some of the ways...
Curated OER
Geometric Shape Dances
Students use movement and dance in order to strengthen mathematical understanding of different geometric shapes. The movements are imitating the drawing of shapes and they pick one to make into a dance. Upon beginning the dance music can...
Mathematics Vision Project
Module 6: Congruence, Construction, and Proof
Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This unit...
Physics Classroom
Kelper's Three Laws
A flipped classroom lesson introduces astrophysics fanatics to Kepler's three laws of planetary motion. After reading about the laws of ellipses, equal areas, and harmonies, and also learning how Newton's gravitation concepts come into...
Curated OER
Origami Ducks: Geometry, Listening, and Following Directions
Make origami ducks with your class to reinforce geometry concepts and vocabulary; develop fine motor and visual translation skills; and enrich study of Japanese culture, the pond habitat, or migration. Create a whole group "worksheet"...
Curated OER
Geometry Straws
Students create different angles and shapes by using different lengths of straws. In this geometry straws lesson plan, students glue straws onto paper and define what they have made.
Curated OER
Pop Quiz for Chapter 2 (Nouns)
In this parts of a sentence interactive worksheet, students recognize nouns in sentences. Students answer ten multiple choice questions relating to nouns.