Worksheet
Curated OER

Congruent Triangles

For Students 10th
In this geometry worksheet, 10th graders identify the corresponding parts of congruent triangles.  The one page worksheet contains four problems.  Answers are not provided. 
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...
Worksheet
Curated OER

Congruent Shapes

For Students 3rd - 4th
In this math activity, students read about congruent shapes. Students also count the congruent parts in 9 different shapes.
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

Symmetry of Road Signs

For Teachers 8th - 11th
Students identify symmetry in road signs. In this geometry lesson, students explore objects in the real world for symmetry. They perform translation, rotation and reflection.
Lesson Plan
Curated OER

Group Isomorphisms

For Teachers 9th - 10th
Students identify and apply properties of triangles. In this geometry lesson, students define equilateral triangles by sides and angles. They build cardboard triangles as they study properties of triangles.
Lesson Plan
Curated OER

Design a Colonial Garden

For Teachers 3rd - 5th
Students explore botany by completing an art design activity in class. In this gardening history lesson, students identify the plants and crops utilized in the Colonial era for both food and medicine. Students utilize geometry to create...
Unit Plan
Massachusetts Department of Education

Similarity through Transformations

For Teachers 9th - 12th Standards
Create the ultimate miniature golf course. The 93-page model curriculum unit from the Massachusetts Department of Elementary and Secondary Education contains nine lessons on understanding similarity in terms of both Euclidean geometry...
Interactive
Scholastic

Study Jams! Lines of Symmetry

For Students 3rd - 5th Standards
Line up this lesson when introducing symmetry to your young mathematicians. Watch how two figures are introduced to different ways of folding and identifying whether or not they are actually symmetrical. Finish the lesson with a...
Lesson Plan
Curated OER

Congruency Basics

For Teachers 4th
Fourth graders investigate congruent shapes. In this congruency lesson, 4th graders explore examples of congruent shapes. Students determine how to check for congruency by sliding or flipping the shape.
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...
Lesson Plan
EngageNY

Base Angles of Isosceles Triangles

For Students 9th - 10th Standards
Build confidence in proofs by proving a known property. Pupils explore two approaches to proving base angles of isosceles triangles are congruent: transformations and SAS. They then apply their understanding of the proof to more complex...
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
Curated OER

Drawing Figures

For Teachers 3rd
Third graders draw shapes that are congruent. In this congruency lesson plan, 3rd graders use grid paper to draw letters and figures and their congruent partners. They complete a worksheet while working in a whole class setting with the...
Lesson Plan
Curated OER

An Application of Congruence

For Teachers 9th - 10th
Learners solve triangles using the properties if congruency. In this geometry lesson plan, students apply congruent and similar figures to solve real world and math problems. They show they are able to follow instructions.
Lesson Plan
Curated OER

Congruent Triangles

For Teachers 9th - 12th Standards
Students identify properties of triangles. In this geometry lesson, students differentiate between similar and congruent triangles. They use the umber of sides to help define the angle of the polygon.
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 instructional activity, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.
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

Reflections

For Teachers 9th - 10th Standards
Facilitate creativity in your math class as individuals learn the definition of a geometric reflection and correctly construct a model, as well as its reflected image. They use a perpendicular bisector and circles to elaborate on...
Lesson Plan
Shodor Education Foundation

Visual Patterns in Tessellations

For Teachers 7th - 10th Standards
Geometers explore the concept of tessellations. They use a tessellation applet to manipulate shapes and design their own tessellation using the applet.
Lesson Plan
EngageNY

Using Unique Triangles to Solve Real-World and Mathematical Problems

For Students 7th Standards
How can congruent triangles help mark a soccer field? This is just one question your classes can answer after solving the real-world problems in the lesson plan. Each example posed through a word problem elicits higher-order thinking and...
Lesson Plan
EngageNY

Unique Triangles—Two Sides and a Non-Included Angle

For Students 7th Standards
Construct an understanding of triangle congruence through a visual analysis. Young scholars find that given two sides and a non-included angle, sometimes two possible triangles are produced. Their analysis shows that if the non-included...
Lesson Plan
EngageNY

More About Similar Triangles

For Teachers 8th Standards
Determine whether two triangles are similar. The lesson presents opportunities for pupils to find the criterion needed to show that two triangles are similar. Scholars use the definition of similarity to find any missing side...
Lesson Plan
EngageNY

Conditions for a Unique Triangle—Three Sides and Two Sides and the Included Angle

For Students 7th Standards
Building on the previous lesson in the 29-part series, the ninth lesson asks individuals to construct a triangle given specific criteria. First, they are given three specific side lengths, followed by two sides and the included angle....