Curated OER
Proofs of the Pythagorean Theorem
Working individually and collaboratively, geometers gain a clear understanding of the Pythagorean theorem. They create, explain, and compare proofs of the theorem. Proofs involve areas of trapezoids, squares, and triangles, congruent...
EngageNY
The Angle-Angle (AA) Criterion for Two Triangles to Be Similar
What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...
Curated OER
A Different Point of View
Elementary schoolers utilize a pattern worksheet embedded in this plan to work on a deeper understanding of geometric concepts like symmetry and congruency. Since geometry is such a visual form of mathematics, this lesson should fit...
West Contra Costa Unified School District
Investigating Special Right Triangles
Scholars first investigate relationships in the side lengths of 30°-60°-90° triangles and 45°-45°-90° triangles. This knowledge then helps them solve problems later in the lesson plan about special right triangles.
Curated OER
Quadrilaterals
In this solving quadrilateral word problems worksheet, students apply knowledge of congruent shapes to problem solve. Students solve six problems.
Curated OER
The Pythagorean Theorem Lesson 2
Learners discuss and review examples of the Pythagorean Theorem using a GSP, Geometer's Sketchpad, activity.
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,...
Curated OER
SuperShapes, Part 1; "Tri"ing Triangles
An outstanding lesson on triangles awaits your math scholars. Learners focus on the triangle, which is the strongest of all polygons. They see the role that triangles play in the design of buildings, and learn about triangle...
Curated OER
Marshmallow Geometry
In this three-dimensional shapes geometry lesson, learners identify geometric solids and name their properties. They define "face," "edge," and "vertex," and construct geometric solids using marshmallows as vertices and toothpicks as edges.
Curated OER
Geo Jammin' By DeSign - Day 1, Lesson 4: Transformation Station
Second graders manipulate triangles to discover the concepts of slides, flips and turns of a geometric shape.
Willow Tree
Three-Dimensional Figures
Time to move into the third dimension! Learn the names of the geometric solids and count faces, edges, and vertices. Then learn to recognize nets that create a given solid.
Willow Tree
Common Geometric Figures
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons.
Curated OER
As the Bird Flies
Students investigate the properties of lines and congruent triangle theorems as well as apply geometric properties and relationships to real-world mathematical problems. Given two different scenarios, they examine maps that have been...
Mathed Up!
Angles: Parallel Lines
Viewers are presented with seven problems with parallel lines and angle relationships and must use the given information to find the measures of specific angles. To finish, they explain their process in finding the measures in the...
Scholastic
Study Jams! Classify Quadrilaterals
Face the vertex of two-dimensional shapes and discover what each figure requires as part of its classification. With one shape per slide, learners see what makes each shape special and compare it to others with similar qualities.
Curriculum Corner
8th Grade Math Common Core Checklist
Ensure your eighth graders get the most out of their math education with this series of Common Core checklists. Rewriting each standard as an "I can" statement, this resource helps teachers keep a record of when each standard was...
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...
Concord Consortium
Mirror, Mirror I
How do you see yourself? Young mathematicians consider whether it's possible to view their whole bodies in a mirror with a length that is half their height. They write a letter to a friend explaining their positions mathematically.
Corbett Maths
Constructing SAS Triangles
Two sides and an angle ... a triangle it makes. Given the measure to two sides and the angle between them, the narrator of a short video shows how to draw a triangle with a ruler and protractor. Pupils use handouts to practice the newly...
Curated OER
Figure This
Second graders identify congruent figures and match shapes using transformation. They work in groups, utilizing a worksheet imbedded in this plan to gain practice identifying congruent shapes.
Curated OER
Slides, Flips, and Turns
In this transformation worksheet, 5th graders determine if a pair of figures are related by a slide, flip, or turn. The worksheet reviews rotation, reflection, and translation.
Curated OER
Splitting the Penstock
Students investigate the best way to calculate the measurements of an area. In this geometry lesson, students relate a large circle to a cylinder and its measurements. They use PVC pipes to gain hands on experience as they calculate the...
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.
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.