Lesson Plan
EngageNY

Informal Proof of the Pythagorean Theorem

For Students 8th Standards
Prove the Pythagorean Theorem using multiple informal proofs. Scholars first develop an understanding of the origins of the Pythagorean Theorem through proofs. They round out the lesson by using the theorem to find missing side lengths...
Lesson Plan
Curated OER

Algebra 2 & Trigonometry Practice: Law of Sines

For Teachers 9th - 12th
In this law of sines worksheet, students solve 9 multiple choice and short answer problems.  Students use the law of sines to missing side lengths and angles of triangles.
Worksheet
Curated OER

Polygon Sum Conjecture

For Students 10th
For this geometry worksheet, 10th graders identify the missing angles using the polygons sum conjecture. They measure exterior and interior angles using their angle theorems. There are 63 problems.
Lesson Plan
Curated OER

Review of Triangles

For Teachers 8th - 10th
Learners investigate the Pythagorean Theorem. In this geometry lesson, students define angles and sides of right triangles. They calculate the area and surface area using formulas derived by the Pythagorean Theorem.
Worksheet
Curated OER

Properties of Angles

For Students 10th
In this properties of angles worksheet, 10th graders solve and complete 3 different types of problems. First, they calculate the value of the missing angles in each diagram and explain the reasons for their answer. Then, students...
Worksheet
Curated OER

Measurement

For Students 7th - 9th
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...
Worksheet
Curated OER

Applied Trigonometry Problems

For Students 9th - 12th
In this applied trigonometry problems worksheet, students solve 12 short answer word problems. Students use trigonometric ratios to find angles of elevation and depression. Students find distances between objects using trigonometric...
Worksheet
Curated OER

Inverse Functions in Trigonometry

For Students 9th - 10th
In this inverse functions in trigonometry activity, students find the missing angles in eight right triangles, given the length of two sides.
Lesson Plan
Curated OER

Trig functions and Triangles

For Teachers 7th - 9th
Here is a basic plan for the beginning teacher to use for introducing the class to the right triangle trigonometric functions. It outlines the lesson objectives, class procedures, and basic instructional techniques that could be...
Assessment
Inside Mathematics

Hopewell Geometry

For Teachers 9th - 12th Standards
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Lesson Plan
Curated OER

Triangle Exterior Angles Theorem

For Teachers 7th - 9th
Students identify the measure of missing exterior angles. In this geometry instructional activity,students define and apply the exterior angle theorem to solve problems. They use Cabri software to create different angles and make...
Lesson Plan
Curated OER

Investigating Trigonometric Ratios Through Similar Right Triangles

For Teachers 9th - 10th
Pupils identify similar and congruent right triangles. In this geometry lesson, students use trigonometric ratios to identify missing sides and angles of a triangle. They differentiate similar and congruent triangles.
Lesson Plan
Curated OER

Triangle Conjectures

For Teachers 10th
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by...
Worksheet
Curated OER

Similar Figures

For Students 7th - 10th
In this similar figure worksheet, students find the length of a missing side of given triangles and quadrilaterals.  This six-page worksheet contains 24 problems.  Answers are provided on the last page.
Worksheet
Curated OER

Pythagorean Theorem

For Students 9th - 10th
In this Pythagorean theorem worksheet, students solve and complete 20 different problems that include using the Pythagorean theorem to solve them. First, they use the Pythagorean theorem to determine the value of x in each right...
Worksheet
Curated OER

Tangents

For Students 9th - 12th
In this tangents activity, learners determine the length of a missing side of a right triangles.  They use tangent lines to solve problems.  This two-page activity contains 11 multi-step problems.
Worksheet
Curated OER

The Law of Sines

For Students 9th - 12th
In this law of sines worksheet, learners use the law of sines to find the missing measurement in a triangle. They determine the value of angles and the lengths of triangles. Students compute the area of triangles. This four-page...
Unit Plan
Mathematics Vision Project

Module 5: Modeling with Geometry

For Students 9th - 12th Standards
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...
Unit Plan
Mathematics Vision Project

Module 7: Modeling with Geometry

For Teachers 9th - 12th Standards
Model good modeling practices. Young mathematicians first learn about cross sections and solids of revolution. They then turn their attention to special right triangles and to the Laws of Sine and Cosine.
Worksheet
Curated OER

Right Triangle Trigonometry

For Students 12th
In this trig worksheet, 12th graders identify the angles of a tight triangle using sine, cos and tan combined with the given sides. There are 23 problems broken down in 4 sections.
Lesson Plan
Curated OER

Triangles Congruency Theorems

For Teachers 10th
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson plan, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed...
Lesson Plan
Utah Education Network (UEN)

It's All Just Similar to Me

For Teachers 7th - 8th
Middle schoolers explore the concept of similar figures. In this similar figures lesson, pupils calculate scale factors of similar triangles. They find missing sides of triangles, and measure angles using protractors and measure sides of...
Lesson Plan
Curated OER

Light Bounce

For Teachers 9th - 11th
Learners solve problems involving triangles. In this geometry lesson plan, students apply properties of triangles to find the missing angles and sides. They identify angles of parallel lines cut by a transversal.
Lesson Plan
Curated OER

Law of Sines

For Teachers 10th - 12th
In this Law of Sines worksheet, students describe, in their own words, when to use the law of sines. They give an example of a problem using the law of sines. This two-page worksheet contains one problem and a sample answer.