Interactive
Scholastic

Study Jams! Similar Figures

For Students 5th - 8th Standards
Discover how triangles are congruent based on their sides, angles, and proportionality. Learners explore the ways to determine similarity at their own pace, and then they practice afterwards with an assessment. 
Lesson Plan
Willow Tree

Ratios and Proportions with Congruent and Similar Polygons

For Students 8th - 11th Standards
Investigate how similar and congruent figures compare. Learners understand congruent figures have congruent sides and angles, but similar figures only have congruent angles — their sides are proportional. After learning the...
Interactive
Scholastic

Study Jams! Congruent Figures

For Students 4th - 7th Standards
There is more to congruency than just looking similar. Learn the difference and calculate the matching angles and sides to prove the congruence between figures. Lesson has step-by-step slides and follows with an assessment. 
Lesson Plan
EngageNY

Solve for Unknown Angles—Transversals

For Teachers 9th - 10th Standards
Lead your class on an exciting journey through the world of math as they review geometry facts and solve for unknown angles. They learn how to use auxiliary lines and congruent angles to correctly complete each practice problem...
Unit Plan
Mathematics Vision Project

Module 6: Congruence, Construction, and Proof

For Teachers 8th - 10th Standards
Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This...
Lesson Plan
Curated OER

Similarity and Dilations - Discover Properties of Similar Figures

For Teachers 9th - 12th Standards
Learners investigate properties of similar figures. In this properties of similar figures lesson, pupils construct similar figures using Cabri Jr. They dilate their figure to create a similar one, and discuss the relationships between...
Lesson Plan
EngageNY

Correspondence and Transformations

For Teachers 9th - 10th Standards
Looking for a strategy to organize the information related to transformations? The materials ask pupils to identify a sequence of rigid transformations, identify corresponding angles and sides, and write a congruence statement. They...
Unit Plan
Virginia Department of Education

Classifying Angles

For Teachers 4th - 8th Standards
Don't be obtuse, this geometry unit is the just the right resource for educating the acute young minds in your class. From classifying and measuring angles, to determining the congruence of shapes, this...
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...
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. 
Printables
Curated OER

Anticipation Guide: Similar and Congruent

For Students 6th - 8th Standards
Find out what your mathematicians know about similar and congruent figures with this anticipatory guide that includes five agree or disagree with statements.    
Lesson Plan
EngageNY

Applications of Congruence in Terms of Rigid Motions

For Students 9th - 10th Standards
Corresponding parts, congruent parts, congruent corresponding parts—what does it all mean? The resource challenges pupils to identify corresponding parts for pairs of figures. It uses examples of figures that undergo rigid...
Lesson Plan
Virginia Department of Education

Constructions

For Teachers 9th - 11th Standards
Pupils learn the steps for basic constructions using a straightedge, a compass, and a pencil. Pairs develop the skills to copy a segment and an angle, bisect a segment and an angle, and construct parallel and perpendicular lines.
Lesson Plan
Virginia Department of Education

Congruent Triangles

For Teachers 9th - 11th Standards
Is this enough to show the two triangles are congruent? Small groups work through different combinations of constructing triangles from congruent parts to determine which combinations create only congruent triangles. Participants use the...
Worksheet
Mt. San Antonio Collage

Circles

For Students 9th - 12th Standards
Don't circle around the topic, but get right to the center with tons of practice regarding circles in geometry. The note-incorporated activity provides guided practice through many topics such as central angles, inscribed polygons...
Lesson Plan
West Contra Costa Unified School District

Congruent and Similar Polygons

For Teachers 9th - 12th
What's similar about congruent and similar polygons? Young mathematicians first measure the side lengths and angles of given figures. They use these measurements to determine relationships between side lengths and angles of congruent and...
Worksheet
Curated OER

Triangle Congruence

For Students 8th - Higher Ed
In this triangle congruence worksheet, students review 4 triangle congruence properties and 4 examples. Students are then prompted to complete 15 problems analyzing whether two triangles are congruent and determine by which property.
Lesson Plan
EngageNY

How Do Dilations Map Angles?

For Students 9th - 10th Standards
The key to understanding is making connections. Scholars explore angle dilations using properties of parallel lines. At completion, pupils prove that angles of a dilation preserve their original measure. 
Lesson Plan
Virginia Department of Education

Similar Figures

For Teachers 7th
How similar do figures have to be to be similar figures? Individuals learn to identify similar figures by verifying that angles are congruent and sides are proportional. Additionally, they match the corresponding parts of similar figures.
Lesson Plan
Curated OER

Congruent Polygons: Copying Stretchy Shapes

For Teachers 3rd
Third graders investigate congruent polygons through dance. In this congruency lesson, 3rd graders do the "brain dance" as a warm up. They review polygon names by singing "The Polygon Chant," before mirroring congruent shapes with a...
Workbook
1
1
University of Utah

Geometry: Transformations, Congruence, and Similarity

For Students 8th Standards
Rigid motions are to congruence as what are to similarity? Investigate properties of rigid motions and define congruence in terms of rigid motions with the ninth chapter of a 10-part eighth grade workbook series. The...
Worksheet
Mt. San Antonio Collage

Isosceles Triangles and Special Line Segments

For Students 9th - 12th Standards
Under which conditions can a triangle be classified as isosceles? High schoolers practice identifying isosceles triangles and special line segments, including angle bisectors, medians of triangles, and perpendicular bisectors of sides of...
Lesson Plan
Curated OER

Geometry Practice: G.G.28 #1: Congruent Triangles

For Teachers 9th - 12th
In this congruent triangles worksheet, students solve four multiple choice problems. Students determine which statement is the appropriate reasoning to say that two triangles are congruent.
Lesson Plan
1
1
Illustrative Mathematics

Right Triangles Inscribed in Circles I

For Teachers 9th - 10th Standards
One of the basic properties of inscribed angles gets a triangle proof treatment in a short but detailed exercise. Leading directions take the learner through identifying characteristics of a circle and how they relate to angles and...