Learners investigate properties of similar figures. For 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...

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...

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...

How similar do figures have to be to be similar figures? Individuals learn to identify similar figures by verifying that angles are congruent and sides are proportional. Additionally, they match the corresponding parts of similar figures.

Middle and high schoolers perform transformations. In this web based lesson, students explore dihedral figures. They use the web tools to translate, rotate, and reflect figures. Pupils identify lines of symmetry.

Group that class and get them classifying and sorting figures as congruent or similar. They use magazines to identify and label similar and congruent figures, cutting out images and placing c or s next to each image.

Eighth graders explore congruent and similar figures.  For this eighth grade geometry lesson, 8th graders use geoboards to create congruent and similar figures and explore the relationships between the sides and angles. 

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...

Does the symmetry and transitive property apply to similarity? The 10th segment in a series of 16 presents the class with a group of explorations. The explorations have pairs show that similarity is both symmetrical and transitive....

Use the coordinate plane to show two figures are similar. The instructional activity incorporates congruence transformations and dilations to move a figure on to another figure. Pupils determine that if a similarity...

Congruence and similarity apply to functions as well as polygons. Learners examine the effects of transformations on the shape of parabolas. They determine the transformation(s) that produce similar and congruent functions.

Build a definition of congruence from an understanding of rigid transformations. The lesson asks pupils to explain congruence through a series of transformations. Properties of congruence emerge as they make comparisons to these...

Fifth graders identify lines of symmetry., similar and congruent shapes. They use construction paper to create their own symmetrical shapes. Students create stained glass frames containing symmetrical, congruent and similar shapes.

Develop a more precise definition of similar. The lesson begins with an informal definition of similar figures and develops the need to be more precise. The class learns about dilations and uses that knowledge to arrive at a...

Students use similar triangles to find missing heights.  In this using similar triangles to find missing heights lesson, students use proportions to find the heights of missing side lengths.  Students find the height of trees...

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...

Learners explore the concept of similarity and congruence. In this similarity and congruence lesson, students identify and verify whether or not two figures are similar, congruent, or neither. Learners use postulates and theorems such as...

Your learners will make good use of the Socratic method in a collaborative task that begins with an assumed solution and ends with deeper understanding of the idea of determining two triangles congruent.

Students determine that two figures are similar or congruent by investigating figures that are similar and figures that are congruent. They prove that two figures are similar or congruent by using definitions, postulates, and theorems.

Tenth graders explore congruent triangles.  In this geometry instructional activity, 10th graders investigate the conditions necessary to prove two triangles congruent.  The instructional activity combines dry erase board...

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.

Pupils describe the differences between congruence and similarity. After explaining the motions that indicate congruency of two shapes, they complete worksheets to draw lines of symmetry and similar shapes. With straws and twist ties,...

While it may seem incredibly obvious to the geometry student that congruent sides make congruent triangles, the proving of this by definition actually takes a bit of work. This exercise steps the class through this kind of proof by...

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.