Activity
Teach Engineering

Stay in Shape

For Teachers 7th - 9th Standards
Using their knowledge of right triangles, pupils find out how far a ship is from a light house. Class members determine how far around the world a ship would be sailing at a constant speed.
Lesson Plan
Curated OER

Exploring and Using Shapes to Make a Dance

For Teachers 2nd
Second graders use their bodies to create various shapes to make a dance when given various music and beats. In this shapes and dance lesson plan, 2nd graders create lines, curves, twists, and angles with their bodies.
Worksheet
Lone Star College

Geometry Worksheet II

For Students 7th - 10th Standards
Young geometers get practice with the algebra of angles in an extensive skills practice worksheet. Supplementary, complementary, and vertical angle relationships are used, along with parallel lines cut by a transversal and angle sum...
Lesson Plan
Curated OER

Angles and Similarity

For Teachers 9th - 12th Standards
Students identify triangles as similar or congruent. For this geometry lesson, students drag triangles around on the navigator to see the effect of different angles on the shape of the triangle. They discuss angle similarity and angle...
Worksheet
Curated OER

Trigonometric Triangles

For Students 9th - 11th
In this trigonometry worksheet, students find the missing angle and sides given the 6 trigonometric values. There are 6 questions with an answer key.
Lesson Plan
Curated OER

Congruent Trianges - Is This Enough Information?

For Teachers 7th
Seventh graders determine whether two triangles are congruent and provide an explanation to why they are not. They apply concepts of measurement of angles and collect evidence of congruent angles in the world.
Lesson Plan
Curated OER

Radian Measure

For Teachers 9th - 12th Standards
Young mathematicians identify central angles, arcs and radius of circles in this pre-calculus lesson. They identify the proportion of the circle based on its radius while they convert between degrees and radians measurements.
Lesson Plan
Curated OER

Corresponding Parts of Similar Triangles

For Teachers 9th - 12th Standards
Here is a lesson that has learners take a look at corresponding parts of similar triangles, ratios of similarity, reductions and enlargements. They'll manipulate the scale factor (r) to observe the changes in similar triangles and then...
Lesson Plan
Curated OER

Reference Angles

For Teachers 9th - 12th Standards
Learn how to measure the reference angles in degrees and radians.  High schoolers find reference angles that are coterminal with a given angle.
Lesson Plan
Curated OER

Triangles

For Teachers 5th - 6th
Students draw triangles. In this shapes lesson, students discuss what they already know about triangles, what they are and what they are made up of. Students discuss the types of triangles and practice drawing each type.
Lesson Plan
Curated OER

Triangles

For Teachers 5th - 6th
Students discover the difference between triangles. In this triangle lesson plan, students discuss the different types of triangles, then draw the three different types of triangles. The teacher will draw, or model, how to draw the...
Worksheet
Curated OER

Using Slope Angles

For Students 10th
In this geometry worksheet, 10th graders use right triangle trigonometry to solve problems involving angle of elevation or depression. The one page worksheet contains eleven problems. Answers are not provided. 
Worksheet
Curated OER

Geometry Worksheet: Angle (2)

For Students 9th - 11th
In this geometry learning exercise, students find the measure of missing angles.  They identify alternate angles.  This one-page learning exercise contains two problems.
Unit Plan
PBS

Accessible Shapes

For Teachers 6th - 8th Standards
All the 2-D and 3-D measurement work you need is in one location. Divided into three sections, the geometry lesson plans consist of visualization of three dimensions, classifying geometric figures, and finding surface area and volume....
Lesson Plan
EngageNY

Using Trigonometry to Find Side Lengths of an Acute Triangle

For Students 9th - 10th Standards
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems. 
Assessment
Noyce Foundation

Parallelogram

For Teachers 6th - 7th Standards
Parallelograms are pairs of triangles all the way around. Pupils measure to determine the area and perimeter of a parallelogram. They then find the area of the tirangles formed by drawing a diagonal of the parallelogram and compare their...
Lesson Plan
Curated OER

Applying Special Right Triangles

For Teachers 10th
In this geometry worksheet, 10th graders use the theorems regarding right triangles to find the missing length in a special right triangle. The one page worksheet contains eleven questions. Answers are included.
Interactive
Curated OER

Shapes and Angles

For Students 4th
Are your geometry whizzes learning about angles and shapes? This online activity gives 10 multiple choice questions based on images and word problems. Concepts include deducting angle degree, classifying shapes, and identifying angle...
Lesson Plan
Utah Education Network (UEN)

Finding Missing Lengths of Similar Triangles

For Teachers 7th - 10th
Middle and high schoolers explore the properties of similar triangles. In this geometry lesson, pupils play a similarity basketball game, sketch similar triangles, and find the missing measures of similar figures. They find the height of...
Lesson Plan
Arizona State University

Tricorn Triangles

For Teachers K - 1st Standards
Help your learners examine triangles. Pupils explore the different sizes and measurements of triangles. They discover triangles can be isosceles or scalene, and examine the attributes of triangles. Here is the website where you can...
Lesson Plan
Curated OER

Similarity and Dilations - Discover Properties of Similar Figures

For Teachers 9th - 12th Standards
Learners investigate properties of similar figures. For this properties of similar figures lesson, pupils construct similar figures using Cabri Jr. They dilate their figure to create a similar one, and discuss the relationships between...
Assessment
Mathematics Assessment Project

Hopewell Geometry

For Students 8th - 10th Standards
Right triangles from 2,000 years ago? Learners investigate different right triangles found in the earthworks of the Hopewell people, a Native American culture that populated the United States from 200BC to AD 500. Learners apply concepts...
Worksheet
Curated OER

Constructing Triangles

For Students 5th - 6th
In this constructing triangles online worksheet, students construct thirteen triangles on paper first and then type in their answers on line. Students can check their answers as they go and the computer calculates the overall score for...
Interactive
Curated OER

Angles in a Triangle

For Students 9th - 12th
In this online math worksheet, students calculate the angles in a triangle given their measurements. This excellent resource allows the students to check their answers, and to get "hints" should they run into difficulties. A terrific...