Lesson Plan
Curated OER

Tessellation Trial and Error

For Teachers 5th - 8th
In this interactive lesson, students review attributes of equilateral polygons. They are introduced to the concept of a tessellation. Using protractors and pre-cut shapes, students arrange a variety of tiles to create tessellations. They...
Interactive
Curated OER

Angles in a Triangle

For Students 10th
In this geometry worksheet, 10th graders determine the measure or measures of the missing angle(s) in a triangle. The one page interactive worksheet contains four questions. Answers and hints are included. 
Worksheet
Curated OER

Geometry Worksheet #13

For Students 10th
For this geometry worksheet #13 worksheet, 10th graders work in groups to solve 6 geometry problems, involving measurement of angles.
Worksheet
Curated OER

Cosine

For Students 10th
In this cosine worksheet, 10th graders solve 10 different problems that include various measures of angles. They determine the value of x in each problem using the cosine of the given angle. Then, students substitute the answer they...
Worksheet
Curated OER

Triangle Review

For Students 5th - 6th
In this triangle review learning exercise, students define what type of triangle is being described, then draw a picture of it. A reference web site is given for additional activities.
Worksheet
Curated OER

Trigonometry

For Students 10th - 12th
In this right triangles worksheet, students use trigonometric ratios to determine the length of a side of a triangle or a missing angle measurement.  This two-page worksheet contains 20 problems.
Worksheet
Curated OER

Shapes and Designs

For Students 10th
In this shapes and designs worksheet, 10th graders solve and complete 6 different types of problems. First, they fill in the first two columns of the table show with their shapes. Then, students measure the interior angles of each...
Lesson Plan
Curated OER

Properties of the Centers of a Triangle

For Teachers 9th - 12th Standards
High schoolers investigate properties of the four centers of a triangle and explore a special property of the circumcenter and orthocenter of a triangle. This instructional activity requires the use of Cabri, Jr.
Lesson Plan
Curated OER

Triangles with Collinear Circumcenters

For Teachers 9th - 10th
Learners identify the circumcenter of a triangle. In this geometry lesson, students construct a perpendicular bisector using a straight edge and a compass. They differentiate between triangles and collinear points.
Worksheet
Lane Community College

Review Sheets: Geometry

For Students 8th - 11th
Full of problems with polygons, angles, lines, and triangles, your learners get a multi-page packet that provides all they need to know. It contains many of the standard problem types as well as some more challenging questions. 
Lesson Plan
Curated OER

Twenty-Five Measures of the Angles of a Triangle Problems

For Teachers 9th - 10th
In this triangle worksheet, students calculate the measures of the angles or the sums of the measures of the angles in twenty-five triangle problems and hands-on activities.  The solutions are provided.
Lesson Plan
Curated OER

Triangle Exterior Angles Theorem

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

Whatcha Gunna Do When the Hulkster's Measuring Too??

For Teachers 8th - 10th
Learners measure using tools they have made. In this algebra lesson, students measure the height and distance using non-traditional measuring methods. They apply their findings to algebra and trigonometry properties of measurements.
Lesson Plan
Curated OER

Exploring Angle Pair Relationships

For Teachers 9th - 11th
Students investigate the relationship between angles of triangles. In this geometry lesson, students identify properties of right and non-right triangles. They differentiate between vertical and supplementary angles.
Lesson Plan
Curated OER

Triangles Introduction

For Teachers K - 3rd
Students explore geometry by drawing various shapes in class. In this triangle characteristics lesson, students identify the attributes that classify a shape as a triangle and practice using their bodies to create triangles in class....
Lesson Plan
Curated OER

Sum of Interior/Exterior Angles with Wilbur

For Teachers 7th - 10th
Students identify the interior and exterior measures of polygons. In this geometry lesson, students identify the formula for interior angles of polygons. They differentiate between triangular and polygons angles.
Lesson Plan
Curated OER

Pythagorean Theorem

For Teachers 9th - 12th
Students identify a right angle and right triangle. They perform WebQuests searching for similar figures and solve for the length of one of the sides given the other two.
Lesson Plan
Curated OER

Scalene Triangles

For Teachers 5th
Fifth graders identify and classify scalene, equilateral, and isosceles triangles. In this triangle lesson, 5th graders define the different attributes of 3 types of triangles and sort them by descriptions and...
Worksheet
Curated OER

Understanding Angles

For Students 9th - 11th
In this geometry learning exercise, students identify the different measure of each angle. They rotate the rays around and make observations about the angles formed. There are 15 questions and lots of examples.
Lesson Plan
Curated OER

Right Triangles and Unit Circles

For Teachers 9th - 11th
Students evaluate the six trigonometric values of a trig function. In this trigonometry lesson plan, students use the Unit Circle to find the values of right triangles and their angles. They identify an angle of elevation and...
Lesson Plan
Curated OER

Inscribed Right Triangles

For Teachers 7th - 9th
Learners calculate the measurements of the inscribed angles of a triangle. For this geometry lesson, students relate the hypotenuse of a right triangle and the diameter of a circle to each other. They calculate the diameter of a circle...
Lesson Plan
Curated OER

Interior and Exterior Angles of Polygons

For Teachers 9th - 10th
Students identify interior and exterior angles of polygons. In this geometry lesson, students add interior and exterior angles of polygons. They use angle theorems to solve the problems.
Lesson Plan
Curated OER

Pythagorean Theorem: Triangles and Their Sides

For Teachers 8th - 10th
Students investigate triangles and their relationship to each other. In this geometry activity, students solve right triangles using the properties of the Pythagorean Theorem. They differentiate between right, acute, straight and oblique...
Lesson Plan
Curated OER

Solving Right Triangles

For Teachers 10th - 11th
Learners investigate the basic trigonometric functions.  In this geometry/trigonometry lesson plan, students explore strategies to solve right triangles using basic trigonometric functions.  The lesson plan includes an...