Curated OER
Building Congruent Triangles
Students differentiate between congruent and similar triangles. In this geometry lesson, students identify the lengths and angle measures of triangles. They use postulates to prove their answers.
Curated OER
2-D and 3-D Presents at Pedro's Party
Fifth graders draw 2-D and 3-D shapes. They sketch and label geometric figures with correct terminology, then explore parallel and perpendicular lines. Pupils sort and classify shapes drawn.
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
Curated OER
Can You Name That Shape?
Learners use materials to build, investigate, and draw two-dimensional shapes (polygons). They combine the shapes they have built and draw from the pile to begin a round-robin activity to name and determine the attributes of a selection...
Virginia Department of Education
Lines and Angles
Explore angle relationships associated with transversals. Pupils construct parallel lines with a transversal and find the measures of the angles formed. They figure out how the different angles are related before constructing...
Curated OER
Unit Squares and Triangles
This is an interesting geometry problem. Given the figure, find the area of a triangle that is created by the intersecting lines. The solution requires one to use what he/she knows about coordinate geometry, as well as triangle and angle...
Curated OER
Corresponding Parts of Similar Triangles
Here is a lesson that has learners take a look at corresponding parts of similar triangles, ratios of similarity, reductions and enlargements. They'll manipulate the scale factor (r) to observe the changes in similar triangles and then...
Curated OER
Volume Of Tetrahedron With Congruent Faces
Ninth graders investigate the concept of a tetrahedron and how it is formed with its congruent faces. They practice making the shape by practicing the folding paper to create the shape. Students continue the instructional activity with...
Curated OER
Transformations: Reflections
Young scholars perform transformations on their graphs. In this algebra lesson, students identify the pre-image and image. They find and identify congruent shapes and isometry.
Shodor Education Foundation
Visual Patterns in Tessellations
Geometers explore the concept of tessellations. They use a tessellation applet to manipulate shapes and design their own tessellation using the applet.
EngageNY
Modeling with Polynomials—An Introduction (part 1)
Maximizing resources is essential to productivity. Class members complete an activity to show how math can help in the process. Using a piece of construction paper, learners construct a box with the maximum volume. Ultimately, they...
Curated OER
Similar or Not?
Fifth graders define the meaning of similar and congruent using concrete objects. They make similar and congruent figures using geoboards. They draw their figures on dot paper, and color their designs.
Curated OER
Medieval Mathematicians and Whimsical Windows
Third graders demonstrate their mathematical knowledge of symmetry and reflection using congruent geometric shapes while working as an artist and mathematician looking at a medieval-styled stained glass window.
Curated OER
Fractions and Halves
Fourth graders examine halves of a whole and discover through activities that they must be exactly equal in size. Working with Geoboards and Dot-Paper Squares, the class practices finding halves that are both congruent and incongruent.
Exploratorium
Cut-Fold-Staple
Here is an interesting activity that combines paper folding art and geometry. In it, learners have a stack of index cards that are bound together. They draw a shape on it, and cut out the shape. When they unfold their shape, they have...
Curated OER
Line Symmetry
Students investigate the concept of line symmetry and how to recognize it in different contexts. They record the number of symmetries when given problems to work on in class. They review the concept of congruence and how it relates to...
Curated OER
Quilt Geometry
Seventh graders explore lines of symmetry, congruent polygons and patterns. They listen to "The Seasons Sewn," observe a PowerPoint presentation, and identify congruent polygons and visual patterns. Through an internet activity, 7th...
Curated OER
Snowflake Curve
Young scholars develop an appreciation for complex structures in nature. They observe patterns in nature in relationship to the Real World. Students use observation skills to assist in problem solving. They show comprehension of the...
Curated OER
Investigating Area and Perimeter of Polygons.
Student sinvestigate the area and perimeter of polygons. They differentiate between similar and congruent polygons.. They identify the ratio and proportions of the sides and angles of polygons.
Curated OER
Tessellations: Geometry and Symmetry
Students explore the concept of tessellations. In this tessellations lesson, students use an applet to construct tessellations. Students use regular polygons to construct tessellations. Students find patterns and symmetry in their...
Curated OER
Shape and Figure Descriptions
In this shape and figures instructional activity, 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.
Virginia Department of Education
Similar Triangles
Pupils work in pairs to investigate what it takes to prove that two triangles are similar. They work through various shortcuts to find which are enough to show a similarity relationship between the triangles. Small groups work with the...
EngageNY
Similarity and the Angle Bisector Theorem
Identifying and verifying reproducible patterns in mathematics is an essential skill. Mathematicians identify the relationship of sides when an angle is bisected in a triangle. Once the pupils determine the relationship, they prove it to...
Annenberg Foundation
Geometry 3D Shapes: Platonic Solids
From polyhedrons to platonic solids, here is a lesson that will have your classes talking! As an introduction to platonic solids, scholars cut and fold nets to create the three-dimensional solids. They use an interactive component to...