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
The Triangles Problem
In this geometry worksheet, 10th graders explain how two triangles can have 5 parts of the other triangle and still not be congruent. This is a word problem with an answer key.
Curated OER
The Truth About Triangles And Proofs
Students engage in a lesson that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the importance of...
Curated OER
Triangle Inequality Theorem
Students use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
Curated OER
Fractals
Students explore the concept of fractals. In this fractal instructional activity, students use applets to explore Koch's Snowflake, Sierpinski's Triangle, and other fractals. Students develop these concepts through exploration and...
Curated OER
Dilation
Tenth graders identidy and define various geometry terms, Students create exact replicas of a shape that is either smaller or larger than the original shape. Students prove that their entire shapes are larger or smaller in the same...
Curated OER
Dream Bedroom Floor Plan
Students build and apply concepts of geometry. In this geometry lesson, students create a building using proportions and scale drawings. They use Cabri technology to create a virtual drawing first.
Curated OER
Dream Bedroom Floor Plan
Students construct using Cabri software. In this geometry lesson, students convert between units and apply the correct measurements to build objects. They create the room virtually and manipulate the shapes to the desired measurements.
Curated OER
Rotations
Young scholars discuss the concepts of reflection, rotation, and translation. In this rotation activity, students investigate rotations through examples on an overhead projector. No additional worksheet or student assignment is included.
Texas Education Agency
Texas Gateway: Generalizing Geometric Properties of Ratios in Similar Figures
Students will investigate patterns to make conjectures about geometric relationships and apply the definition of similarity, in terms of a dilation, to identify similar figures and their proportional sides and congruent corresponding...
CK-12 Foundation
Ck 12: Interactive Geometry: 6.3 Aa Triangle Similarity
If two triangles are similar, it means that all corresponding angle pairs are congruent and all corresponding sides are proportional. However, in order to be sure that two triangles are similar, you do not necessarily need to have...
Other
Nearpod: Similar Figures & Proportionality
In this lesson on similar figures and proportionality, students explore how to identify if figures are similar by applying their knowledge of corresponding angles and sides.
Texas Instruments
Texas Instruments: Similar Figures Discovery Activity
Students can use Cabri Jr. to discover two properties of similar triangles: corresponding angles are congruent and corresponding sides are proportional.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.7 Applications of Similar Triangles
Learn how similar triangles have congruent corresponding angles and proportional corresponding sides.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.5 Sss Triangle Similarity
Explore and understand two triangles that are similar.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.4 Sas Triangle Similarity
Explore and understand triangle similarity.
Sophia Learning
Sophia: Similarity
This learning tutorial describes the characteristics of similar figures and how to use scale factor and proportions to determine missing side lengths. The lesson includes PowerPoint presentations and videos demonstrating how to solve...
Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: Similarity
This site contains a lesson plan for high school age learners. The objective is to discover the factor of proportionality in similar polygons and to relate this factor to the perimeters and areas of similar polygons.
Sonoma State University
Sonoma State University: Parallel Lines and Similar and Congruent Triangles
This site defines eleven theorems relating to parallel lines and similar and congruent triangles. Links to the theorems and relevant term descriptions are provided.
Sophia Learning
Sophia: Corresponding Parts: Lesson 5
This lesson will define the phrase corresponding parts (e.g. angles, sides, etc.). It is 5 of 5 in the series titled "Corresponding Parts."
Sonoma State University
Sonoma State University: Parallel Lines and Similar and Congruent Triangles
This site defines parallel lines, parallel lines cut by a transverse, and congruent triangles. It also contains links for related terms.
Texas Instruments
Texas Instruments: Math Today Ballooning Inside the Box
In this activity Using the USATODAY infograph, "Ballooning inside the box", students will explore geometric relationships using similar triangles. Identifying triangles with two pairs of congruent angles to explore similarity properties...