EngageNY
Informal Proof of AA Criterion for Similarity
What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply...
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...
Curated OER
Similar Triangles - Geometry Exploration
Eighth graders become engaged in a instructional activity in geometry to improve mathematical skills. They construct triangles, segments, and points using Geometer's Sketchpad to demonstrate how dilations of triangles and rectangles...
Curated OER
Let the Matrix Do It
Students create a matrix of the vertices of a triangle and produce new matrices that dilate, translate, rotate, and reflect the original triangle. After multiplying each matrix by a new scale factor, they graph the new matrix and...
Curated OER
Introduction to Unit V-Transformations
Students investigate transformations. In this Algebra I/Geometry lesson, students explore reflections, translations, rotations and dilations. The lesson includes examples of transformations in art, architecture, and nature.
Curated OER
Effect of Transformations on Coordinates
For this effect of transformations on coordinates worksheet, learners determine the coordinates of 4 geometric shapes on a grid after a given transformation.
Curated OER
Geometry Scavenger Hunt
Young scholars use the digital camera, identify geometric shapes (in nature as well as man-made), and gain a better understanding of geometric vocabulary. They search for and recognize geometric shapes in unusual settings
Virginia Department of Education
Middle School Mathematics Vocabulary Word Wall Cards
Having a good working knowledge of math vocabulary is so important for learners as they progress through different levels of mathematical learning. Here is 125 pages worth of wonderfully constructed vocabulary and concept review cards....
NTTI
Transform Your Geometry into a Work of Art
Mathematicians utilize artwork to help illustrate the major ideas of transformations and tessellations. They visually identify transformations including reflections, rotations, and translations. They discuss how artists have used...
Curated OER
Transformational Geometry Using the Geometer's Sketchpad
Students complete a webquest on the various types of symmetry. Using a computer, they explore the concepts of transformational geometry and identify points, segments, lines and planes. They experiment with the rotation of a quadrilateral...
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
Punch Patterns
Fifth graders duplicate patterns, guess pattern results and identify the symmetries created. They are given an instructional handout, 5th graders replicate the patterns demonstrated by folding the paper and punching the appropriate...
Curated OER
Design Explorations: Frieze Patterns
Young scholars will explore frieze patterns. A frieze pattern is a mathematical concept to classify designs on two-dimensional surfaces, which are repetitive in one direction, based on the symmetries in the pattern. They will explore...
Curated OER
Angle Exploration and Classification
Students compare and contrast angles and identify them as acute, obtuse, right, or straight angles. They create rays and angles using uncooked spaghetti, read and discuss key vocabulary terms, and complete a variety of geometry worksheets.
Curated OER
Determine the Coordinate of Transformations
Students investigate transformation on a coordinate plane. In this geometry lesson, students identify pairs of coordinates and their location on the grid. They perform rotation and reflection of each polygon.
Curated OER
Data Representation
Learners solve real life scenarios using math. In this geometry lesson, students collect, predict and interpret data. They measure a chair using different measurements and choose what would make the chair the best design.
Curated OER
Triangle Tango: Special Right Triangles
Learners investigate properties of special right triangles. In this geometry instructional activity, students use the Pythagorean Theorem to solve for missing angles and sides. They perform reflections.
