Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Noyce Foundation
Photographs
Scaling needs to be picture perfect. Pupils use proportional reasoning to find the missing dimension of a photo. Class members determine the sizes of paper needed for two configurations of pictures in the short assessment task.
West Contra Costa Unified School District
Congruent and Similar Polygons
What's similar about congruent and similar polygons? Young mathematicians first measure the side lengths and angles of given figures. They use these measurements to determine relationships between side lengths and angles of congruent and...
Willow Tree
Ratios and Proportions with Congruent and Similar Polygons
Investigate how similar and congruent figures compare. Learners understand congruent figures have congruent sides and angles, but similar figures only have congruent angles — their sides are proportional. After learning the...
Scholastic
Study Jams! Lines of Symmetry
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 multiple...
Charleston School District
Constructing Dilations
Pupils multiply the vertical and horizontal distances from the center of dilation by the scale factor. The independent practice prompts the class to analyze the relationship between the image and pre-image. The lesson is part three in a...
Charleston School District
Review Unit 2: Congruence and Similarity
Review for the test with a comprehensive list of terms and concepts for the unit on congruence and similarity. It divides divides the sections in the order of the lessons presented during the unit.
Charleston School District
Identifying Series and Determining Congruence or Similarity
Learners consider a set of questions to determine a series of transformations that will move one figure to another. Once the series is determined, the pupil then determines whether the pre-image and image are either congruent or similar.
Charleston School District
Pre-Test Unit 2: Similar and Congruent
A pre-test contains questions about transformations that lead to congruent and similar images. It also covers angle relationships associated with triangles and parallel lines intersected by a transversal.
EngageNY
General Pyramids and Cones and Their Cross-Sections
Are pyramids and cones similar in definition to prisms and cylinders? By examining the definitions, pupils determine that pyramids and cones are subsets of general cones. Working in groups, they continue to investigate the relationships...
Scholastic
Study Jams! Congruent Figures
There is more to congruency than just looking similar. Learn the difference and calculate the matching angles and sides to prove the congruence between figures. Lesson has step-by-step slides and follows with an assessment.
Scholastic
Study Jams! Similar Figures
Discover how triangles are congruent based on their sides, angles, and proportionality. Learners explore the ways to determine similarity at their own pace, and then they practice afterwards with an assessment.
Curated OER
Anticipation Guide: Similar and Congruent
Find out what your mathematicians know about similar and congruent figures with this anticipatory guide that includes five agree or disagree with statements.
Curated OER
Similar Shapes
In geometry, similar and congruent shapes are often confused. Shapes that are similar are the same shape, but a different size. This activity gives young learners some practice in identifying similar shapes. There are five polygons...
Curated OER
Dihedral Figures
Middle and high schoolers perform transformations. In this web based lesson, young scholars explore dihedral figures. They use the web tools to translate, rotate, and reflect figures. Pupils identify lines of symmetry.
Curated OER
Visual Analogies
Here are four questions which require learners to examine four pairs of visual analogies and then choose a figure that completes a missing part of an analogy that is the same as the one shown. They then get to create their own visual...
Curated OER
Dilations and Similarity
In this dilations and similarity worksheet, pupils solve 10 different problems that include various dilations. First, they determine the scale factor of dilations found in the illustrated graphs. Then, everyone determines the coordinates...
Curated OER
Similarity and Dilations - Discover Properties of Similar Figures
Learners investigate properties of similar figures. In this properties of similar figures lesson, pupils construct similar figures using Cabri Jr. They dilate their figure to create a similar one, and discuss the relationships between...
Everyday Mathematics
Mathematics Within: Slope and Triangles
Learners discover a method for determining the slope of a line by creating and comparing similar triangles. They fold coordinate grids to make three similar triangles then measure the sides to compare the relationships between the...
Curated OER
Similar Triangles and Trapezoids, and Circles
High schoolers answer two problems involving area of shaded regions. High schoolers then answers six questions involving perimeter, area, and circumferences. The remaining two questions involve ratios of similar figures.
Curated OER
Comparing 3-D Shapes
How is a sphere like a prism? Learners compare and contrast 3-D shapes, first drawing each in the boxes provided. If this is too advanced, supply pre-cut images of the shapes for students to choose from and glue onto the instructional...
Curated OER
Similarity: Instructional
In this similarity learning exercise, students solve and complete 7 different problems that include determining various dimensions of mirrors shown. First, they find the length of the diagonal of the large mirror in the diagram. Then,...
Virginia Department of Education
Similar Solids and Proportional Reasoning
Double the dimensions, quadruple the surface area. Pairs build similar prisms and compare the ratios of their surface areas and volumes to the ratio of the heights. Given two similar cones, partners determine the ratios of the lateral...
Curated OER
Exploring Similarity Using Scale Drawings
Learners explore scale factor as they create a scale drawing of a box, then determine the surface area and volume of the original and the scale drawing. The one page worksheet contains activities and procedures with four questions.