Virginia Department of Education
Angles in Polygons
Polygons — it's all about the angles. Groups work with dynamic geometry software to find the sum of the measures of the angles of various polygons. After finding the information for several polygons, the groups generate a formula that...
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...
02 x 02 Worksheets
Symmetry
Get learners' minds rotating and reflecting while looking for symmetry. Pupils investigate figures to determine the number of lines of symmetry and if the figure has rotational symmetry. Classmates work together in groups to find out the...
Annenberg Foundation
Geometry 3D Shapes: Euler's Theorem
How do you get a theorem named after you? Euler knows what it takes! The third lesson of five asks pupils to use an interactive activity to compare the faces, vertices, and edges of seven different three-dimensional solids. They use...
Curated OER
Transformations and Translations in Geometry
In this transformations and translations in Geometry worksheet, learners use geometric shapes and grids to translate six transformations in each of two activities.
Exploratorium
String Shapes
You'd never have guessed it, but simple pieces of string make a fabulous manipulative for the study of geometry! In the fine lesson plan here, young mathematicians use string to make a variety of polygons. Pupils sit in various...
Virginia Department of Education
Properties of Quadrilaterals
What type of quadrilateral is that? Discover the difference between the types of quadrilaterals. Small groups investigate types of quadrilaterals using geometry software to find their properties. To keep track of the different...
Shodor Education Foundation
Transmographer
Introducing ... the Transmographer. Young mathematicians investigate translations, reflections, and rotations. The applet lets users perform transformations on triangles, squares, and parallelograms.
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...
Virginia Department of Education
Special Right Triangles and Right Triangle Trigonometry
Right triangles are so special! Use special right triangles to discover the trigonometric ratios. Pairs construct special right triangles and find the values of the ratios of the sides. In the process, they discover the ratios stay the...
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
Stressed and Strained
Students explore stress and strength in engineering design. In this engineering lesson, students become familiar with terminology associated with stress and strain on building material. They will have a class discuss about how their beam...
Virginia Department of Education
Angles, Arcs, and Segments in Circles
Investigate relationships between angles, arcs, and segments in circles. Pupils use geometry software to discover the relationships between angles, arcs, and segments associated with circles. Class members use similar triangles to...
Curated OER
How High Is That?
Students explore the National Spatial Reference System. In this vertical position lesson, students will discuss the use of vertical position data and solve practical problems involving geographic positioning.
Curated OER
Golden Ratio
Tenth graders investigate the Golden Ratio. In this geometry lesson, 10th graders explore the Fibonacci sequence in the context of The Fibonacci Rabbit problem. Students examine how the ratio of two consecutive Fibonacci number create...
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.