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...
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
Students calculate the measurements of the inscribed angles of a triangle. In this geometry activity, 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
Young scholars 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 lesson, 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
Young scholars investigate the basic trigonometric functions.  In this geometry/trigonometry lesson, students explore strategies to solve right triangles using basic trigonometric functions.  The lesson includes an application...
Lesson Plan
Curated OER

Patterns in the Sums of Polygon Angles

For Teachers 6th
Sixth graders discover the patterns of sums of polygon angles. In this math lesson, 6th graders study the properties of geometric shapes to solve problems as they participate in hands-on activities.
Lesson Plan
Curated OER

Why can't We Use SSA to Prove Triangles Congruent?

For Teachers 9th - 10th
Students investigate triangles and congruences. In this geometry lesson, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.
Lesson Plan
Curated OER

Trig River

For Teachers 6th - 8th
Students calcute distances using trigonometry and angle measurements. They estimate the width of the Trig River, measure it and compare their results with their classmates. They collaborate with a group to research and find the results.
Lesson Plan
Curated OER

Pythagorean Theorem

For Teachers 7th - 8th
Students discover the Pythagorean Theorem.  In this discovering the Pythagorean Theorem lesson plan, students measure the lengths of various triangles to the nearest centimeter. Students record their measurements in a table. ...
Lesson Plan
Curated OER

Pythagorean Theorem

For Teachers 8th
Eighth graders draw right triangles and identify the parts of a right triangle: right angle, interior and exterior angles, hypotenuse and legs. They predict and identify any relationships that exist between the sides of a right...
Lesson Plan
Curated OER

Tomb Robbers

For Teachers 6th
Sixth graders identify benchmark angles as they are embedded into a circle grid. They observe the teacher using an angle ruler and complete a Star Spangled worksheet, play the game Tomb Robbers, and as a class discuss their game winning...
Lesson Plan
Curated OER

Flip's Flag

For Teachers 5th
Fifth graders apply the symmetry and angle properties of polygons and use fractions to express the relationships between the areas of rectangles, squares, and triangles. They analyze various country flags and develop mathematical...
Lesson Plan
Curated OER

Investigating Area Relationships

For Teachers 9th - 12th Standards
Learners investigate the area of various figures. They construct triangles and quadrilaterals using Cabri Jr. and discuss the relationships between different angles, side lengths, and figures.
Lesson Plan
Curated OER

Midsegments of Quadrilaterals

For Teachers 9th - 12th Standards
High schoolers explore the concept of quadrilaterals as they find the midsegments of quadrilaterals using Cabri Jr. on a graphing calculator. They find midpoints, slopes, angles, and distances of lines and angles.
Lesson Plan
Curated OER

Reflections Of

For Teachers 4th - 6th
Students create angles using mirrors. In this angle reflection lesson, students draw angles, then use mirrors to create angles using reflections and measure the new angles.
Lesson Plan
Willow Tree

The Pythagorean Theorem

For Students 8th - 11th Standards
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...
Lesson Plan
Willow Tree

Common Geometric Figures

For Students 8th - 11th Standards
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons. 
Lesson Plan
EngageNY

Writing and Solving Linear Equations

For Teachers 8th Standards
Incorporate geometry into the solving linear equations lesson. Pupils use their knowledge of geometry to write linear equations which reinforces geometry measurement concepts while at the same time providing a familiar context for...
Lesson Plan
EngageNY

Review of the Assumptions (part 2)

For Students 9th - 10th Standards
Is the amount of information getting overwhelming for your geometry classes? Use this strategy as a way to organize information. The resource provides a handout of information studied in relation to triangle congruence. It includes a...
Lesson Plan
EngageNY

Cyclic Quadrilaterals

For Teachers 9th - 12th Standards
What does it mean for a quadrilateral to be cyclic? Mathematicians first learn what it means for a quadrilateral to be cyclic. They then investigate angle measures and area in such a quadrilateral.
Lesson Plan
Virginia Department of Education

Side to Side

For Teachers 6th
Congruent figures: two figures that want to be just like each other. Individuals learn to distinguish between figures that are congruent and those that are not. Measuring the lengths of line segments and angles helps in this endeavor.