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 lesson with the estimation...
Curated OER
Transformations: Reflections
Learners perform transformations on their graphs. For 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.
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
Learners explore the concept of tessellations. In this tessellations lesson, students use an applet to construct tessellations. Learners use regular polygons to construct tessellations. Students find patterns and symmetry in their...
Curated OER
Shape and Figure Descriptions
For 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.
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...
Curated OER
Symmetry and Tangrams
Sixth graders build figures out of tangrams. In this symmetry instructional activity, 6th graders view tangrams and identify the polygons included in them. Students divide into groups, identify their tangram pieces, define the lines of...
Pennsylvania Department of Education
Rotational Symmetry of Polygons and Other Figures
Students explore geometry by participating in a shape rotation experiment. For this symmetry lesson, students identify the term symmetry and a list of other geometry vocabulary. Students analyze shapes as they are turned 90 degrees and...
Curated OER
Identifying Lines of Symmetry and Creating Reflections over a Line
Fifth graders review the concept of a line of symmetry by using pieces of paper that have pictures such as, letters of the alphabet, polygons, and designs made from polygons in order to determine if they have symmetry. The fine, two-hour...
Curated OER
Three- and Two- Dimensional Geometry
In this three- and two- dimensional geometry worksheet, 7th graders solve 12 various problems related to geometric shapes and measurement. They first use paper and a pencil to sketch the front, side, back, top and bottom views of each...
Curated OER
Toe to Toe Geo
Students study triangles. In this triangle lesson plan, students compare and classify triangles while milling to music. Students will also trade triangles so they can match up with other similar triangles. Triangles are provided.
Curated OER
Geometric Transformations
Learners examine images and preimages of a mapping and identify isometry. They view images by M.C. Escher, observe teacher demonstrations, and create a translation image, a rotation image, and a dilation.