Curated OER
Incenter of a Triangle
Tenth graders find the incenter of a triangle. In this geometry lesson, 10th graders define the way to create an incenter with an angle bisector. They differentiate between incenter and incircle.
Willow Tree
Perimeter of Common Geometric Figures
Help learners understand that perimeter and circumference are one in the same. Learners apply their skills to determine the perimeter/circumference of triangles, rectangles, and circles. They then use the same strategy to find the...
GeoGebra
Triangle Dilations
Stretch the class' knowledge of dilations. With the aid of the rubber band stretcher tool, learners perform dilations. They dilate the triangle by a whole number scale and a fractional scale from two centers of dilation.
Curated OER
Triangle Inequality Theorem
High schoolers investigate the relationship between angle measures and sides of a triangle and the relationships among the three sides of a triangle. The use of technology (Cabri, Jr.) allows learners to make and test conjectures as they...
Los Angeles County Office of Education
Assessment For The California Mathematics Standards Grade 6
Test your scholars' knowledge of a multitude of concepts with an assessment aligned to the California math standards. Using the exam, class members show what they know about the four operations, positive and negative numbers, statistics...
Curated OER
Chords of a Circle
Teach how to differentiate between chords and perpendicular bisectors. In this geometry lesson, students relate the properties of chords and circle to solving right triangle. They define what makes two chords congruent in side a circle.
EngageNY
End-of-Module Assessment Task - Grade 8 Mathematics (Module 3)
Everything the class knows about similarity in one small package. The last portion of a 16-part series is a three-question assessment. In it, pupils demonstrate their application of similar figures and their associated...
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
Concord Consortium
Orthogonal Circles
Here's some very interesting circles for your very interested pupils. A performance task requires scholars to sketch a pair of orthogonal circles so the centers are the endpoints of one side of a triangle. They draw an additional circle...
Mathematics Assessment Project
Applying Angle Theorems
Polygon ... an empty bird cage? After finding the angles of a polygon, young mathematicians use the provided methods to solve the problem in multiple ways.
Curated OER
You Can't Go Wrong with a Right Triangle 1
Fourth and fifth graders study the Pythagorean Theorem and apply it to find the missing side of a right triangle.
Education Development Center
Similar Triangles
Model geometric concepts through a hands-on approach. Learners apply similar triangle relationships to solve for an unknown side length. Before they find the solution, they describe the transformation to help identify corresponding sides.
K12 Reader
Classifying Triangles
Bring math and reading informational text together with a reading comprehension lesson. After kids read about isosceles, scalene, and equilateral triangles, they answer five comprehension questions to demonstrate how they can use context...
Curated OER
Reflections and Equilateral Triangles II
Given the lines of symmetry in an equilateral triangle, your learners find where the pre-image vertices are mapped onto the new image. They explore the properties of equilateral triangles, the impact of reflections, and the...
Mathematics Assessment Project
Calculating Volumes of Compound Objects
After determining the volume of various drinking glasses , class members evaluate sample responses to the same task to identify errors in reasoning.
Curated OER
Dilations in the Plane
Tenth graders investigate dilations and explore the dilation transformation before investigating the properties of a dilation using Cabri Jr. Students extend the concept of dilatation to the coordinate plane.
Curated OER
Chapter 7 Final Review Extra Problems: Triangles
For this triangles worksheet, students respond to 4 short answer problems. Students describe side relationships of different types of triangles. Students find the area of a segment formed by a sector.
Curated OER
Special Right Triangles
In this special right triangle worksheet, students use the trigonometric functions to determine angle measurement or the length of one side of a right triangle. This one-page worksheet contains 18 problems. Answers are provided at the...
Willow Tree
Common Geometric Figures
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons.
Curated OER
Reflected Triangles
Your learners find and construct the line of reflection between a triangle's pre-image and its reflection image in this short activity.
Curated OER
Inscribing a Circle in a Triangle
Pupils investigate inscribing a circle in a triangle. They use Cabri Jr. to draw a triangle, locate the incenter, and use the distance from the incenter to a side of the triangle to inscribe a circle. The dynamic nature of the geometry...
EngageNY
Sequencing Rotations
Discover the result of a sequence of rotations about different centers. Pupils perform rotations to examine the patterns. They also describe the sequence of rotations that performed to reach a desired result in the ninth installment in a...
American Farm Bureau Foundation for Agriculture
Shapes on the Farm
Whether you live in the city, the suburbs, or out on the farm, shapes are everywhere in the world around us. Presented with an illustration of a farm, youngsters are tasked with coloring in all of the triangles,...
Mathematics Assessment Project
Modeling Motion: Rolling Cups
Connect the size of a rolling cup to the size of circle it makes. Pupils view videos of cups of different sizes rolling in a circle. Using the videos and additional data, they attempt to determine a relationship between cup...