Lesson Plan
Willow Tree

Angles Formed by Transversals of Coplanar Lines

For Students 8th - 11th Standards
Create a strong understanding of the relationships formed when parallel lines intersect a transversal. Discuss each type of angle pair and their relationship to each other. 
Lesson Plan
EngageNY

General Pyramids and Cones and Their Cross-Sections

For Teachers 9th - 10th Standards
Are pyramids and cones similar in definition to prisms and cylinders? By examining the definitions, pupils determine that pyramids and cones are subsets of general cones. Working in groups, they continue to investigate the relationships...
Activity
Illustrative Mathematics

Reflections and Isosceles Triangles

For Teachers 9th - 11th Standards
Geometers explore symmetries of isosceles triangles by using rigid transformations of the plane. They complete four tasks, including congruence proofs, which illustrate the relationship between congruence and rigid transformations. The...
Activity
Illustrative Mathematics

Is This a Parallelogram?

For Teachers 9th - 12th Standards
If both pairs of opposite sides of a quadrilateral are congruent, is the quadrilateral a parallelogram? This task asks learners to determine the answer and to support their answer with a proof. The resource includes a commentary for...
Interactive
Curated OER

Similar Triangles Multiple Choice

For Students 8th - 10th
In this triangle relationships worksheet, students identify measurements in similar and congruent triangles. Each problem features a drawing of two or more triangles. Students identify missing measurements. There are 5 multiple choice...
Worksheet
Curated OER

Symmetry Fun

For Students 7th
In this symmetry worksheet, 7th graders identify and complete 12 different lines of symmetry in polygons. First, they color all of the polygons that have a line of symmetry. Then, students circle all of the regular polygons and use the...
Lesson Plan
EngageNY

Law of Sines

For Teachers 11th - 12th Standards
Prove the Law of Sines two ways. The ninth segment in a series of 16 introduces the Law of Sines to help the class find lengths of sides in oblique triangles. Pupils develop a proof of the Law of Sines by drawing an altitude and a second...
Lesson Plan
EngageNY

Properties of Area

For Teachers 9th - 10th Standards
What properties does area possess? Solidify the area properties that pupils learned in previous years. Groups investigate the five properties using four problems, which then provide the basis for a class discussion.
Activity
Noyce Foundation

Part and Whole

For Students K - 7th Standards
Now you'll never have trouble cutting a cake evenly again. Here is a set of five problems all about partitioning shapes into a given number of pieces and identifying the fractional amount of each piece. As learners progress through the...
Worksheet
Curated OER

Parallelograms

For Students 10th
In this parallelograms worksheet, 10th graders identify and describe a quadrilateral, a diagonal, and a parallelogram in 7 different problems. First, they find the values of x, y, and z in each quadrilateral to prove that it is a...
Worksheet
Curated OER

Right Triangles

For Students 10th
In this right triangles learning exercise, 10th graders solve 6 various problems and figures related to right triangles. First they identify and describe the 3 theorems and 1 postulate stated that prove 2 right triangles congruent if one...
Worksheet
Curated OER

Parts of Similar Triangles

For Students 10th
In this parts of similar triangles worksheet, 10th graders solve 6 different problems related to determining the value of various parts of similar triangles. First, they find the value of x in the 2 figures shown. Then, students find the...
Worksheet
Curated OER

Identifying Similar Triangles

For Students 10th
In this identifying similar triangles activity, 10th graders solve 6 different types of problem that include identifying and comparing similar triangles. First, they identify the three ways that determine whether two triangles are...
Worksheet
Curated OER

Properties of Geometry

For Students 10th
In this properties of geometry worksheet, 10th graders solve and complete 12 different problems that include various theorems. First, they draw a figure that illustrates the SAS inequality property. Then, students prove that two line...
Worksheet
Curated OER

Identifying Similar Triangles

For Students 10th
In this identifying similar triangles worksheet, 10th graders solve 5 different proofs related to similar triangles. First, they identify the similar triangles in each figure and explain why they are similar, using the information to...
Worksheet
Curated OER

Angles

For Students 10th
In this angles learning exercise, 10th graders measure 10 different types of angles described in each problem. First, they determine whether two congruent angles form a supplementary figure. Then, students determine the degrees in an...
Lesson Plan
1
1
Illustrative Mathematics

Applying the Pythagorean Theorem in a Mathematical Context

For Teachers 7th - 9th Standards
Participants who use this resource will apply the Pythagorean Theorem to show whether or not the shaded triangle inscribed in a rectangle is a right triangle. Once all of the sides on the shaded triangle are found, it is important that...
Worksheet
Curated OER

Shape and Figure Descriptions

For Students 5th - 6th
In this shape and figures worksheet, students read descriptions of shapes and figures, name them and draw their pictures in spaces provided. A reference web site is given for additional activities.
Worksheet
Curated OER

Perimeter

For Students 10th
In this perimeter worksheet, 10th graders solve and complete nineteen various geometry problems. First, they find the length of given segments in addition to the perimeter of a kite. Then, students find the value of a variable so that...
Worksheet
Curated OER

Why do Stars Rise in the East?

For Students 8th - 10th
In this stars rise in the east worksheet, students use geometry to show how the Earth rotates from west to east and why celestial bodies appear to rise in the east and set in the west. Students draw a figure and label given points in...
Worksheet
Curated OER

Points, Lines and Planes

For Students 10th
In this points, lines and planes worksheet, 10th graders solve and complete 9 various types of problems. First, they name the planes that intersect a figure shown. Then, students determine the points that are collinear and coplanar in...
Worksheet
Mt. San Antonio Collage

Postulates, Angles, and Their Relationships

For Students 8th - 11th Standards
More than a worksheet, learners go through geometry topics example by example on the nicely organized handout. From postulates to classifying angles, there are rules and examples provided for each topic. The ten pages of problems...
Assessment
EngageNY

Mid-Module Assessment Task: Grade 8 Module 2

For Students 8th Standards
It's time for a concept check! Check for student understanding over the three types of rigid transformations. The assessment follows the first 10 lessons in this series and to test pupils' proficiency of these concepts. Individuals...
Assessment
Inside Mathematics

Aaron's Designs

For Teachers 8th Standards
Working with transformations allows the class to take a turn for the better. The short assessment has class members perform transformations on the coordinate plane. The translations, reflections, and rotations create pattern designs on...