Lesson Plan
Curated OER

Congruent and Similar figures

For Teachers 8th
Eighth graders explore congruent and similar figures.  In this eighth grade geometry lesson, 8th graders use geoboards to create congruent and similar figures and explore the relationships between the sides and angles. 
Lesson Plan
Curated OER

Concurrent Lines in Triangles

For Teachers 9th - 12th
Students explore the concept of concurrent lines in triangles. In this concurrent lines in triangles lesson, students work in groups to investigate properties of concurrent lines in acute, right, and obtuse triangles. Students use a...
Worksheet
Curated OER

Right Triangles

For Students 10th
In this right triangles worksheet, 10th graders solve 10 different problems that include determining the means proportionally in each right triangle. First, they use the given information to determine the measure of each line segment....
Worksheet
Curated OER

Similar Triangles

For Students 10th
In this similar triangles worksheet, 10th graders solve and complete 10 different problems related to determining the sides of similar triangles. First, they write three equal ratios to show the corresponding sides that are proportional....
Worksheet
Curated OER

The Triangles Problem

For Students 10th
For this geometry worksheet, 10th graders explain how two triangles can have 5 parts of the other triangle and still not be congruent. This is a word problem with an answer key.
Worksheet
Curated OER

Eighteen SSS or SAS Triangle Congruence Problems

For Students 9th - 10th
In this triangle congruence worksheet, students state if triangles are congruent and if the congruence is based on side, side, side or the side, angle, side theorems in eighteen problems.  The solutions are found on the last two pages.
Worksheet
Curated OER

Congruent Containers

For Students 3rd - 6th
In this congruency worksheet, students find congruency in everyday packaging on everyday items and answer questions about them. Students answer 4 questions.
Worksheet
Curated OER

Geometry and Measurement Pre-Test

For Students 6th - 10th
Use this comprehensive pre-instruction assessment tool to focus your teaching where your class needs it most. Multiple choice questions assess your budding geometers' conceptual and vocabulary knowledge, but they do not solve any...
Lesson Plan
EngageNY

Are All Parabolas Similar?

For Students 10th - 12th Standards
Congruence and similarity apply to functions as well as polygons. Learners examine the effects of transformations on the shape of parabolas. They determine the transformation(s) that produce similar and congruent functions.
Assessment
EngageNY

Mid-Module Assessment Task: Grade 7 Mathematics Module 6

For Students 7th Standards
This is a mid-module assessment for the 16th lesson in 29 geometry lessons. Individuals demonstrate their understanding of concepts such as vertical and adjacent angles, constructing geometric figures, and triangle congruence criteria.
Assessment
1
1
Mathematics Assessment Project

College and Career Readiness Mathematics Test A2

For Students 9th - 12th
A six-page evaluation covers material included in algebra, geometry, and algebra II. Applied word problems are mixed in with short answer questions. It also provides questions on mathematical reasoning.
Lesson Plan
Curated OER

Triangles & Congruence, Proportions & Similarity, Right Triangle & Trigonometry

For Teachers 9th - 12th
Students are introduced to the topic of congruence and proportions in Geometry. Using technology, they construct and validate the properties of various geometric figures and identify whether it is congruent or proportion to the objects...
Lesson Plan
Curated OER

Equilateral Triangles

For Teachers 4th - 5th
Learners examine the attribute of equilateral triangles. In this equilateral triangle lesson, students examine a number of paper triangles to determine how they are classified. They determine how triangles are depicted in Navajo rugs.
Lesson Plan
Curated OER

Similar Triangles

For Teachers 9th
Ninth graders find the height of every day objects using techniques learned through postulates that allow triangles in a problem to be similar. They calculate the length of a missing side and solve proportions.
Lesson Plan
Curated OER

Triangles in Architecture

For Teachers 10th - 12th
Students find triangles in the real world. In this geometry lesson, students analyze and identify properties of two and three-dimensional objects. They differentiate between similarity and congruence.
Worksheet
Curated OER

The Isosceles Triangle Problem

For Students 10th
In this geometry activity, 10th graders solve a problem involving an isosceles triangle.  The problem appears to be deceptively easy, but instead requires the use of trigonometry to arrive at a correct solution.  The one page...
Lesson Plan
Curated OER

NON-EUCLIDEAN GEOMETRY.

For Teachers 8th - 9th
Students study relationships between angles, side lengths, perimeters, areas and volumes of similar objects. In this instructional activity students also create and critique inductive and deductive arguments concerning congruency,...
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

Geometry

For Teachers 9th - 11th
Students are introduced to the basics of Geometry. Using cutout shapes, they identify whether they are polygons by using the properties of polygons. They practice drawing shapes they are going to be using on an everyday basis and...
Lesson Plan
Curated OER

Triangle Attributes and Measures

For Teachers 7th
Seventh graders explore the concept of triangles. In this triangles lesson, 7th graders sort triangles according to various attributes such as acute, obtuse, isosceles, or equilateral. Students find the area and perimeter of triangles.
Lesson Plan
Futures Channel

Folding Circles

For Teachers 7th - 12th Standards
Students investigate properties of circles. In this geometry lesson plan, students differentiate between similarity and congruence as they observe polygons. They investigate properties of two and three dimensional shape.
Lesson Plan
Curated OER

Slides, Flips. Turns......It's All On A Memory Book Page

For Teachers 4th
Fourth graders use tangram sets to investigate the congruence of shapes. They use congruent shapes to demonstrate the properties of slides, flips, and turns. They complete a math journal entry that describes and illustrates each concept.
Lesson Plan
Curated OER

Euclidean Direct Proofs

For Teachers 9th - 10th
Learning how to prove theorems in geometry can be challenging. This resource explains what a proof is, and the different styles for proofs. It also contains links to web-based practice problems that help guide learners though example...
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...