Houghton Mifflin Harcourt
Developing Formulas for Circles and Regular Polygons
Formulas and procedures for finding the area and circumference are not provided on this handout, so it will be best used as a practice of already-acquired skills. It is a well-rounded assignment, however, as it includes diagrams,...
EngageNY
Properties of Tangents
You know about the tangent function, but what are tangent lines to a circle? Learners investigate properties of tangents through constructions. They determine that tangents are perpendicular to the radius at the point of tangency, and...
EngageNY
Equations for Tangent Lines to Circles
Don't go off on a tangent while writing equations of tangent lines! Scholars determine the equations for tangent lines to circles. They attempt both concrete and abstract examples, such as a tangent line to the unit circle through (p, 0).
EngageNY
Ptolemy's Theorem
Everyone's heard of Pythagoras, but who's Ptolemy? Learners test Ptolemy's Theorem using a specific cyclic quadrilateral and a ruler in the 22nd installment of a 23-part module. They then work through a proof of the theorem.
EngageNY
The Inscribed Angle Alternate – A Tangent Angle
You know the Inscribed Angle Theorem and you know about tangent lines; now let's consider them together! Learners first explore angle measures when one of the rays of the angle is a tangent to a circle. They then apply their newfound...
Curated OER
Points, Lines, Planes, and Space
In this points, lines, planes, and space worksheet, students solve word problems dealing with points, lines, planes, and space. Students complete 20 individual problems and 20 group problems.
Education Development Center
Finding Parallelogram Vertices
Four is the perfect number—if you're talking about parallelograms. Scholars determine a possible fourth vertex of a parallelogram in the coordinate plane given the coordinates of three vertices. They read a conversation...
PBS
Using Symmetry to Create Corporate Logos
Young mathematicians investigate the use of symmetry in graphic design. After first learning about reflection, translational, and rotational symmetry, children use this new knowledge to identify symmetry in letters of the alphabet and...
Concord Consortium
City of New Orleans
In the United States, most trains operate at a top speed of 100 miles per hour. Scholars use information on the distance and time of a train trip to determine if the train ever reaches a specific speed. They connect pieces of information...
Curated OER
Distance Calculations
Students calculate the distance between two points. In this geometry lesson, students use coordinates and the distance formula to find the distance. They perform an interactive lesson to solve the missing length.
University of Nottingham
Drawing to Scale: A Garden
See how design and geometry go hand in hand. The activity asks learners to use geometry to design a backyard garden given dimensions of each feature. Scholars work with ratios and scale to develop an accurate scale drawing that includes...
Curated OER
Word Problem Practice Workbook
Need worksheets that challenge your middle schoolers to apply their understanding of math? Problem solved! From integers, fractions, and percents, to algebra, geometry, and probability, over 100 pages of word problem worksheets are...
Noyce Foundation
Once Upon a Time
Examine the relationship between time and geometry. A series of five lessons provides a grade-appropriate problem from elementary through high school. Each problem asks learners to compare the movement of the hands on a clock to an angle...
Learner
Solid Shapes
A collection of two lessons, kindergartners will identify two-dimensional shapes in solid shapes. They will develop basic knowledge of the components that make up a sphere, rectangular prism, pyramid, cylinder, cone, and cube. Young...
K12 Reader
Kinds of Angles
Have you ever wondered how circles and angles relate to each other? Read a passage about right angles, acute angles, and obtuse angles, and answer reading comprehension questions about the information you learn.
Curated OER
Using Properties Homework
In this geometry worksheet, 10th graders determine the property of the real number system that justifies each given statement and complete a two column proof in which they justifying the steps for solving an equation. The one page...
EngageNY
End-of-Module Assessment Task: Grade 8 Module 5
Give your class a chance to show how much they've learned in the module with an end-of-module assessment task that covers all topics from the module including linear and non-linear functions and volumes of cones, cylinders, and spheres.
EngageNY
Trigonometry and Complex Numbers
Complex numbers were first represented on the complex plane, now they are being represented using sine and cosine. Introduce the class to the polar form of a complex number with the 13th part of a 32-part series that defines the argument...
EngageNY
Fundamental Theorem of Similarity (FTS)
How do dilated line segments relate? Lead the class in an activity to determine the relationship between line segments and their dilated images. In the fourth section in a unit of 16, pupils discover the dilated line segments are...
EngageNY
An Area Formula for Triangles
Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....
EngageNY
Examples of Dilations
Does it matter how many points to dilate? The resource presents problems of dilating curved figures. Class members find out that not only do they need to dilate several points but the points need to be distributed about the entire curve...
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...
Alberta Learning
Area and Perimeter of Irregular Shapes
Evaluate young mathematicians' understanding of area and perimeter with this series of three assessment tasks. Challenging students to not only calculate the area and perimeter of irregular shapes, but to explain in writing their...
Curated OER
Transformations on the Coordinate Plane
Here is a study guide on transformations that includes reflections, translations, dilations, and rotations. It also has definitions, helpful diagrams, and several examples involving transformations on the coordinate plane. The lesson...