Lesson Plan
Curated OER

Right Triangles

For Teachers 4th - 8th
Learners classify triangles and make connections regarding angle measurements and attributes of acute, right, and obtuse triangles. They listen to teacher define and explain triangles. Everyone imagines a place where a broken wing for a...
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

Exploring Angle/Pair Relationships

For Teachers 7th - 10th
Students find missing angles and sides of triangles. In this geometry lesson, students create intersecting lines to measure angles. They use Cabri Software to create virtual angles.
Lesson Plan
Curated OER

Investigating a Point on an ANgles Bisector

For Teachers 7th - 9th
Pupils investigate points and angle bisectors. In this geometry lesson plan, students define angles, bisectors and perpendicular bisectors. They analyze angles and bisectors using Cabri software.
Lesson Plan
Curated OER

Exploring Angle Pair Relationships

For Teachers 9th - 11th
Learners 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

Discovering The Ratio Pi And The Diameter

For Teachers 9th - 10th
Students relate the ratio of Pi to the diameter of a circle. In this geometry lesson plan, students investigate the relationship of the chord of the circle the the number Pi. They define ration, chord, circumference and diameter and find...
Lesson Plan
Curated OER

Isosceles Triangles

For Teachers 9th - 10th
Students identify the properties of an isosceles triangle. In this geometry lesson, students find the midpoint, median and angle bisector of a triangle. They construct angle bisectors and measure missing angles.
Lesson Plan
Curated OER

Exploring the Properties of Rectangular Prisms.

For Teachers 9th - 10th
Students define properties of rectangular prisms. In this geometry lesson, students identify the relationship between two and three dimensional objects. They use Cabri technology to graph their figures.
Lesson Plan
EngageNY

From Circle-ometry to Trigonometry

For Students 10th - 12th Standards
Can you use triangles to create a circle? Learners develop the unit circle using right triangle trigonometry. They then use the unit circle to evaluate common sine and cosine values.
Lesson Plan
Mathematics Assessment Project

Solving Problems with Circles and Triangles

For Teachers 9th - 12th Standards
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Lesson Plan
Curated OER

Geometry in Tessellations

For Teachers All
Students examine tessellations and their geometric properties. Students also develop a better understanding of lines, planes, angles, and polygons.
Lesson Plan
Curated OER

Grasping Geometry

For Teachers 3rd - 4th
Students investigate geometric shapes in their environment, make a geometric design, and write paragraphs describing the design.
Lesson Plan
Curated OER

Polygons Defined

For Teachers 4th
Fourth graders explore polygons. In this polygon lesson, 4th graders sort polygons according to their properties. Students discover the connection between polygons and the Greek language.
Lesson Plan
Curated OER

Geometry /Tessellations

For Teachers 6th - 8th
Learners investigate the concept of tessellations and how they are formed using angles. They categorize how different patterns do and not tessellate and separate them into two different places for assessment. The teacher draws examples...
Lesson Plan
Curated OER

Angle-Side Relationships

For Teachers 9th - 12th
High schoolers calculate the different sides and angles of a triangle. In this geometry lesson, students use triangular properties to define the relationship between two triangle. They identify missing angles using the interior angle...
Lesson Plan
Curated OER

Constructing Tangrams

For Teachers 7th
Seventh graders visualize and identify geometric shapes after applying transformations on a coordinate plane. In this tangrams lesson, 7th graders construct a set of tangrams and then answer extension questions related to measurement,...
Lesson Plan
Curated OER

Perimeter

For Teachers 5th
Fifth graders create math word problems. For this geometry lesson, 5th graders define perimeter and discover how to find the perimeter of a rectangle, a square and a regular polygon. Students write word problems on finding the...
Lesson Plan
Curated OER

Area Of Sectors

For Teachers 9th - 12th
Student find the area of a sector of a circle. In this geometry lesson, students  define the sector of a circle using a sketch. They find and identify examples of sector in the real world.
Lesson Plan
Curated OER

Got Complements? with Cabri Jr.

For Teachers 9th - 12th Standards
Learners use the axes and measure angle tool to explore and calculate complementary angles with Cabri Jr. They also identify what happens to the calculation as they drag the endpoint into a different quadrant. Finally, they label each...
Lesson Plan
Curated OER

Regular Polygons

For Teachers 5th
Fifth graders explore polygons. In this math instructional activity, 5th graders find examples of regular polygons in the classroom and measure the sides of figures to determine if they are regular polygons.
Lesson Plan
Curated OER

Similar Triangles - Applied Problems

For Teachers 9th - 12th
Students differentiate between similar and congruent triangles. In this geometry lesson, students identify the angles of triangles using the similarity theorem. They apply concepts of triangles to the real world.
Lesson Plan
Curated OER

Introducing Angles

For Teachers 6th
Sixth graders identify, compare and interpret the characteristics of polygons and angles in order to meet spatial sense, geometry and measurement standards. They also sort shapes into three categories, polygons (regular and irregular)...
Lesson Plan
Curated OER

Isosceles Triangles

For Teachers K - 2nd
Students investigate triangles. In this shapes geometry lesson, students define and state the attributes for equilateral, scalene, and isosceles triangles. Students locate the prefix "tri" in a variety of words and make connections with...
Lesson Plan
Curated OER

Scale factors: Ratios and Proportions

For Teachers 8th - 11th
Pupils create building and models using scale factors. In this geometry lesson plan, students apply the properties of ratio and proportion to solve problems. They identify the means and extremes property of cross multiplication.