Lesson Plan
Curated OER

Inscribed Angles

For Teachers 9th - Higher Ed
Pupils analyze inscribed angles and intercepted arcs and explore the relationships between the two. They investigate the properties of angles, arcs, chords, tangents, and secants to solve problems involving circles.
Worksheet
Curated OER

Naming Angles

For Students 5th - 7th
For this geometry worksheet, students solve 6 problems in which an angle is analyzed. From 5 choices, students circle the correct math symbol that names the angle. There are no examples or explanations for the symbols, which would be...
Worksheet
Curated OER

Calculate Missing Angles and Line Lengths

For Students 5th - 6th
In this missing line length and missing angles worksheet, students find measures of missing angles and find missing lengths. A reference web site is given for additional activities.
Assessment
EngageNY

End-of-Module Assessment Task - Geometry (module 2)

For Students 9th - 10th Standards
Increase the level of assessment rigor with the test of performance tasks. Topics include similar triangles, trigonometric ratios, Law of Sines, Law of Cosines, and trigonometric problem solving. 
Worksheet
Curated OER

Triangle Inequalities

For Students 10th
For this triangle inequalities worksheet, 10th graders solve 10 different problems that include various types of triangles. First, they determine which side is the longest side of a triangle with given the exterior angle measurement....
Lesson Plan
EngageNY

The Angle-Angle (AA) Criterion for Two Triangles to Be Similar

For Teachers 9th - 10th Standards
What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...
Lesson Plan
EngageNY

Using Trigonometry to Find Side Lengths of an Acute Triangle

For Students 9th - 10th Standards
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems. 
Lesson Plan
EngageNY

The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar

For Students 9th - 10th Standards
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice...
Unit Plan
Mathematics Vision Project

Module 5: Circles A Geometric Perspective

For Teachers 9th - 12th Standards
Circles, circles, everywhere! Pupils learn all about circles, central angles, inscribed angles, circle theorems, arc length, area of sectors, and radian measure using a set of 12 lessons. They then discover volume formulas through...
Assessment
Noyce Foundation

Parallelogram

For Teachers 6th - 7th Standards
Parallelograms are pairs of triangles all the way around. Pupils measure to determine the area and perimeter of a parallelogram. They then find the area of the tirangles formed by drawing a diagonal of the parallelogram and compare their...
Lesson Plan
Willow Tree

Common Geometric Figures

For Students 8th - 11th Standards
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. 
Unit Plan
Curated OER

Transformations in the Coordinate Plane

For Teachers 9th - 12th Standards
Your learners connect the new concepts of transformations in the coordinate plane to their previous knowledge using the solid vocabulary development in this unit. Like a foreign language, mathematics has its own set of vocabulary terms...
Lesson Plan
Alabama Learning Exchange

What You Know About the Bermuda Triangle?

For Teachers 9th - 12th Standards
Get lost in the classifications. Using the backdrop of the Bermuda Triangle, pupils classify it by angle and side measures. They also learn information about the triangle and its history.
Assessment
Concord Consortium

Isosceles Triangle Spaces

For Students 7th - 10th Standards
How many different types of triangles can your class name? A discovery lesson guides learners through an exploration of the different triangle types and the relationships between their angles and sides. Using coordinate geometry,...
Lesson Plan
Virginia Department of Education

Constructions

For Teachers 9th - 11th Standards
Pupils learn the steps for basic constructions using a straightedge, a compass, and a pencil. Pairs develop the skills to copy a segment and an angle, bisect a segment and an angle, and construct parallel and perpendicular lines.
Lesson Plan
Virginia Department of Education

Side to Side

For Teachers 6th
Congruent figures: two figures that want to be just like each other. Individuals learn to distinguish between figures that are congruent and those that are not. Measuring the lengths of line segments and angles helps in this endeavor.
Unit Plan
Arizona Department of Education

Area and Perimeter of Regular and Irregular Polygons

For Teachers 3rd - 6th Standards
Extend young mathematicians' understanding of area with a geometry lesson on trapezoids. Building on their prior knowledge of rectangles and triangles, students learn how to calculate the area of trapezoids and other...
Activity
Curated OER

Math Games for Skills and Concepts

For Teachers 2nd - 5th
A 27-page packet full of math games and activities builds on algebra, measurement, geometry, fractional, and graphing skills. Young mathematicians participate in math games collaboratively, promoting teamwork and skills practice.
Lesson Plan
University of Nottingham

Drawing to Scale: A Garden

For Students 6th - 9th Standards
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...
Lesson Plan
EngageNY

Fundamental Theorem of Similarity (FTS)

For Teachers 8th Standards
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...
Lesson Plan
Curated OER

Geometry in the Real World

For Teachers 8th
Eighth graders complete a unit of lessons on basic geometry concepts. They participate in a variety of activities, culminating in a project that involves publishing a booklet or a poster that presents the major geometry concepts from the...
Worksheet
Curated OER

Determine the Measure of an Angle of a Right Triangle.

For Students 10th - 11th
In this geometry worksheet, students solve word problems by finding the values of missing angles and missing sides of triangles. They review their trigonometric properties of a right triangle. There are 9 problems with an answer key.
Worksheet
Curated OER

Geometric Shapes and Angles

For Students 10th
For this geometry worksheet, 10th graders review polygons and solve for the missing angles of trapezoids and isosceles triangles. There are 10 questions on this worksheet with an answer key.
Lesson Plan
Curated OER

Indirect Measurement

For Teachers 9th - 10th
Learners measure and apply their knowledge of proportion to solve problems. In this geometry lesson, students measure using a meter stick, small mirror and measuring tape. They compare and contrast their measurements to objects outside...