EngageNY
Reflections
Facilitate creativity in your math class as individuals learn the definition of a geometric reflection and correctly construct a model, as well as its reflected image. They use a perpendicular bisector and circles to elaborate on...
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
Inscribing a Square in a Circle
Inscribing a square in a circle brings up a number of interesting geometry topics including triangle congruence and how to prove a quadrilateral is a square. This activity is followed up by finding the area of the square and determining...
Illustrative Mathematics
Points equidistant from two points in the plane
Young geometers apply their deductive reasoning skills and knowledge of proving triangles congruent in a task that asks them to prove if a point lies on the perpendicular bisector of a segment, then it is equidistant from the endpoints...
EngageNY
Solve for Unknown Angles—Transversals
Lead your class on an exciting journey through the world of math as they review geometry facts and solve for unknown angles. They learn how to use auxiliary lines and congruent angles to correctly complete each practice problem...
Curated OER
Geo Jammin' By Design - Day 7, Lesson 38: Kool Cups
Create geometric cups by interpreting directions, informational text, and mathematical concepts. Critical thinkers apply geometric theory (congruent shapes, patterns, symmetry) to actual directions to create a cup that holds Kool Aid....
Curated OER
Unit Squares and Triangles
This is an interesting geometry problem. Given the figure, find the area of a triangle that is created by the intersecting lines. The solution requires one to use what he/she knows about coordinate geometry, as well as triangle and angle...
Curated OER
A Different Point of View
Elementary schoolers utilize a pattern worksheet embedded in this plan to work on a deeper understanding of geometric concepts like symmetry and congruency. Since geometry is such a visual form of mathematics, this lesson should fit...
Sargent Art
Color Value Study
I love geometric art because it applies mathematical reasoning to an artistic endeavor. Creative kids use scale values to highlight their complex, repetitive, geometric designs. Symmetry, angles, and congruence are three concepts that...
Curated OER
Math: Shapes and More Shapes
Students locate lines of symmetry in regular polygons and predict the number of lines of symmetry in an octagon. In three different polygons, they construct all lines of symmetry and after making their prediction about the octagon,...
Curated OER
Similar or Not?
Fifth graders define the meaning of similar and congruent using concrete objects. They make similar and congruent figures using geoboards. They draw their figures on dot paper, and color their designs.
Curated OER
Geometry in Tessellations
Students examine tessellations and their geometric properties. Students also develop a better understanding of lines, planes, angles, and polygons.
Curated OER
Basic Geometry Ideas and Angle Measurement
Seventh graders explore the concept of basic geometry. In this basic geometry instructional activity, 7th graders identify the correct picture for a given vocabulary word such as midpoint, line, ray, or parallel lines. Students discuss...
Curated OER
As the Bird Flies
Students investigate the properties of lines and congruent triangle theorems as well as apply geometric properties and relationships to real-world mathematical problems. Given two different scenarios, they examine maps that have been...
Curated OER
Linear/Planar Geometry - Week 5
In this plane geometry worksheet, students combine the basis of plane geometry and linear problems to solve problems. They determine total surface area, the length of a line, and the sum of the edges of a three-dimensional figure. This...
Curated OER
Linear/Planar Geometry - Week 5
In this linear and planar geometry worksheet, students use the Pythagorean Theorem, equation of a line, slope of a line and area formulas to solve problems. This three-page worksheet contains seven problems.
Curated OER
T-Angling with Words
In this geometry roots worksheet, 10th graders solve and complete 22 various types of problems. First, they match the geometry word roots on the left with their meanings found on the right side. Then, students list as many other geometry...
Mt. San Antonio Collage
Circles
Don't circle around the topic, but get right to the center with tons of practice regarding circles in geometry. The note-incorporated worksheet provides guided practice through many topics such as central angles, inscribed polygons and...
El Paso Community College
Geometry Definitions
Geometry is full of shapes, figures, and corresponding things here and there. The guide shares all of the key pieces of geometric information in a nicely color-coded and labeled sheet.
Mt. San Antonio Collage
Postulates, Angles, and Their Relationships
More than a worksheet, learners go through geometry topics example by example on the nicely organized handout. From postulates to classifying angles, there are rules and examples provided for each topic. The ten pages of problems provide...
Illustrative Mathematics
Reflections and Isosceles Triangles
Geometers explore symmetries of isosceles triangles by using rigid transformations of the plane. They complete four tasks, including congruence proofs, which illustrate the relationship between congruence and rigid transformations. The...
Illustrative Mathematics
Midpoints of the Sides of a Paralellogram
This task asks learners to prove that the segment joining the midpoints of two sides of a parallelogram is both congruent and parallel to an adjacent side of the parallelogram. The activity would be good to use in a discussion about how...
Curated OER
Transformations Using the Geometer's Sketchpad
Students discover rules for single transformations, rules for composition of transformations, when a figure has transformation symmetry, and if a transformation is congruent to its preimage.
Illustrative Mathematics
Is This a Parallelogram?
If both pairs of opposite sides of a quadrilateral are congruent, is the quadrilateral a parallelogram? This task asks learners to determine the answer and to support their answer with a proof. The resource includes a commentary for...