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...
Georgia Department of Education
Analytic Geometry Study Guide
Are you looking for a comprehensive review that addresses the Common Core standards for geometry? This is it! Instruction and practice problems built specifically for standards are included. The material includes geometry topics from...
Illustrative Mathematics
How Many Leaves on a Tree?
This is great go-to activity for those spring or fall days when the weather beckons your geometry class outside. Learners start with a small tree, devising strategies to accurately estimate the leaf count. They must then tackle the...
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 worksheet. A...
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.
Curated OER
The Attack of the Manhole Monsters
Students explore the concept of similarity. They examine such topics as ratio of corresponding sides, internal ratios and scaling factors. After watching a video, student groups perform experiments outside the school building.
Curated OER
Exploring Congruent Triangles
For this congruent triangles worksheet, students solve 12 different equations related to writing a correspondence statement for triangles in the given diagrams. They complete each correspondence statement and write a congruence statement...
Futures Channel
Folding Circles
Students investigate properties of circles. In this geometry lesson, students differentiate between similarity and congruence as they observe polygons. They investigate properties of two and three dimensional shape.
Curated OER
Finding Volume of Similar Figures
Upper elementary and middle schoolers examine the Volumes of Similar Figures. They investigate the relationship between corresponding sides and evaluate the volume of similar figures. Pupils record their findings on various activity...
Curated OER
Unit 5: Worksheet 3 - Similar Triangles
In this similar triangles worksheet, students use proportions to solve for the missing sides of similar triangles. This two-page worksheet contains 16 multi-step problems.
Curated OER
Zome System
Get hundreds of interactive activity plans using the Zome Modeling System. Among dozens of lessons, a first exposure to similar triangles can be very visual for the learner. Here, young geometers explore the number of different shapes...
Curated OER
Fractals Teachers' Notes
When you see a flower or a tree in nature do you see the math? This web resource contains many ideas for using fractals in a math class including Sierpinski’s triangle, Koch's Snowflake, and the Jurassic Park Fractal. Additionally, it...
Curated OER
Symmetry and Geometric Shapes on Campus
Build on your learners' previous knowledge of geometric shapes and symmetrical figures. Then set them out to take photos of geometric shapes on campus. They assess whether the photos contain symmetry or not.
Curated OER
Congruent / Similar Shape Cards
Cut apart 16 cards with 8 congruent pairs of geometric shapes, then have your class match the cards which show congruent shapes. There are no directions or information on the page so use your imagination to create a fun activity. Tip:...
Curated OER
Similar Situations
Young scholars explore intersecting lines. In this intersecting lines lesson, students investigate shapes consisting of parallel, perpendicular, and similar lines. Young scholars investigate these lines in shapes around them.