Curated OER
Angles and Similarity
High schoolers identify triangles as similar or congruent. In 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...
Curated OER
Trigonometric Triangles
In this trigonometry worksheet, students find the missing angle and sides given the 6 trigonometric values. There are 6 questions with an answer key.
Curated OER
Congruent Trianges - Is This Enough Information?
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.
Curated OER
Radian Measure
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.
Curated OER
Corresponding Parts of Similar Triangles
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...
Curated OER
Reference Angles
Learn how to measure the reference angles in degrees and radians. Students find reference angles that are coterminal with a given angle.
Curated OER
Triangles
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...
Curated OER
Triangles
Learners draw triangles. In this shapes lesson, students discuss what they already know about triangles, what they are and what they are made up of. Learners discuss the types of triangles and practice drawing each type.
Curated OER
Using Slope Angles
In this geometry instructional activity, 10th graders use right triangle trigonometry to solve problems involving angle of elevation or depression. The one page instructional activity contains eleven problems. Answers are not...
Curated OER
Geometry Worksheet: Angle (2)
In this geometry activity, students find the measure of missing angles. They identify alternate angles. This one-page activity contains two problems.
PBS
Accessible Shapes
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....
EngageNY
Using Trigonometry to Find Side Lengths of an Acute Triangle
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.
Noyce Foundation
Parallelogram
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...
Curated OER
Applying Special Right Triangles
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.
Curated OER
Shapes and Angles
Are your geometry whizzes learning about angles and shapes? This online worksheet gives 10 multiple choice questions based on images and word problems. Concepts include deducting angle degree, classifying shapes, and identifying angle...
Arizona State University
Tricorn Triangles
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...
Curated OER
Similarity and Dilations - Discover Properties of Similar Figures
Learners investigate properties of similar figures. In 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...
Mathematics Assessment Project
Hopewell Geometry
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...
Curated OER
Constructing Triangles
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...
Curated OER
Angles in a Triangle
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...
Curated OER
Drawing a Triangle with Cabri Junior
Learners draw triangles on their graphing calculators using the Cabri Junior application. In this graphing calculator lesson, students follow step by step directions to create triangles on their calculator. They identify the type of...
Curated OER
Drawing Triangles
In this drawing triangles worksheet, 6th graders read the dimensions of four triangles, given the length or the angle, identify the type of triangle and draw it.
Curated OER
Measurement
In this measurement worksheet, students find the value of complementary and supplementary angles. They identify angles, parallel lines, and find the angle measurement of missing angles in a triangle. This one-page worksheet contains 10...
Curated OER
Measurements of Unknown Angles
In this geometry skills practice worksheet, students respond to 9 questions that require them to calculate the measurements of the unknown angles.