Lesson Plan
Curated OER

Studying Special Segments in Triangles

For Teachers 8th - 10th
Young scholars investigate special segments in triangles. In this geometry lesson, students graph, compare, estimate and predict findings based on their data. They differentiate between similarity and congruence of triangles.
Lesson Plan
Curated OER

Geometry of Triangles Using a Protractor

For Teachers 7th
Seventh graders use a protractor to measure angles and solve a problem involving distance. For this measuring angles with a protractor lesson plan, 7th graders calculate the distance of a line on a diagram by using a protractor to...
Lesson Plan
Curated OER

IGD: Perpendicular Bisector

For Teachers 9th - 12th
Students draw perpendicular bisectors.  In this perpendicular bisectors lesson, students identify the perpendicular bisector in a polygon.  They use web tools to create and measure perpendicular bisectors.  Students...
Lesson Plan
Curated OER

Find Someone Who........

For Teachers 5th
Fifth graders identify, describe, and classify lines, line segments, rays, and angles. When given a diagram of a line, they classify the line as perpendicular, parallel, intersecting, vertical, horizontal, and/or diagonal.
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
EngageNY

Cyclic Quadrilaterals

For Teachers 9th - 12th Standards
What does it mean for a quadrilateral to be cyclic? Mathematicians first learn what it means for a quadrilateral to be cyclic. They then investigate angle measures and area in such a quadrilateral.
Lesson Plan
EngageNY

More About Similar Triangles

For Teachers 8th Standards
Determine whether two triangles are similar. The lesson presents opportunities for pupils to find the criterion needed to show that two triangles are similar. Scholars use the definition of similarity to find any missing side...
Lesson Plan
EngageNY

Special Lines in Triangles (part 1)

For Students 9th - 10th Standards
Allow your pupils to become the mathematicians! Individuals explore the properties of a midsegment of a triangle through construction and measurement. Once they figure out the properties, learners use them to draw conclusions.
Lesson Plan
Texas Instruments

Exploring Tangents

For Teachers 9th - 12th Standards
Explore the concept of tangent lines. In this tangent line lesson, learners graph a circle and two lines on their graphing calculator using Cabri Jr. Learners construct the lines so that they both intersect at a given point and are both...
Lesson Plan
Curated OER

Basic Geometry Ideas and Angle Measurement

For Teachers 7th
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...
Lesson Plan
Curated OER

Angle Attributes and Measures

For Teachers 7th
Seventh graders explore the concept of angles. In this angles lesson, 7th graders use protractors to measure angles. Students sing an angle song. Students discuss attributes of angles using a two-color plate manipulative.
Lesson Plan
Curated OER

Angles: Angles, Angles, Everywhere

For Teachers 6th - 8th
Students estimate and accurately measure the size of angles communicate with the appropriate geometric terms and symbols to describe and name angles, lines, line segments, rays
Lesson Plan
Curated OER

Lines, Rays, Line Segments, and Planes

For Teachers 9th - 12th
Students are introduced to lines, rays, line segments and planes and study the differences between them. They also practice graphing lines, rays, line segments and planes
Lesson Plan
Illustrative Mathematics

Two Wheels and a Belt

For Teachers 9th - 10th Standards
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
Lesson Plan
EngageNY

Informal Proof of AA Criterion for Similarity

For Teachers 8th Standards
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...
Lesson Plan
EngageNY

Arc Length and Areas of Sectors

For Teachers 9th - 10th Standards
How do you find arc lengths and areas of sectors of circles? Young mathematicians investigate the relationship between the radius, central angle, and length of intercepted arc. They then learn how to determine the area of sectors of...
Lesson Plan
Curated OER

Trigonometric Ratios

For Teachers 10th - 12th
Young scholars measure and analyze angles. In this trigonometry instructional activity, students measure angles and distances use non-traditional techniques. They identify the different ratios of sine, cosine and tangent.
Lesson Plan
Curated OER

Geometry of Triangles - Week 6

For Teachers 12th - Higher Ed
In this geometry of triangles worksheet, students find the length of sides, are, and angle measurement of inscribed triangles, pentagons, and midpoint of a line. This two-page worksheet contains seven problems.
Lesson Plan
Curated OER

Classifying and Constructing Corners

For Teachers 5th
Fifth graders, after seeing Honeycomb examples, complete a Classifying Angles worksheet, Clock worksheet, and Defining Angles worksheet.
Lesson Plan
Curated OER

The Trig to Soccer

For Teachers 9th - 10th
Students analyze angles applied to a penalty kick in a soccer game. Based on dimensions of the goal, and the penalty area, students determine where the better chance of scoring lies.
Lesson Plan
Curated OER

Geometry Journal: Isosceles Triangles

For Teachers 10th - 12th
In this isosceles triangles worksheet, students justify and determine the symmetry of an isosceles triangle. They explore the bisector of rectangles. This three-page worksheet contains two problems. Answers are listed on page three.
Lesson Plan
Curated OER

Measuring the Earth

For Teachers 10th - 11th
Young scholars identify types of arcs and angles in a circle, find the measure of arcs and angles, and solve real world problems involving lengths of segments in circles, lengths, and areas.
Lesson Plan
Curated OER

Triangle Attributes and Measures

For Teachers 7th
Seventh graders explore the concept of triangles. In this triangles lesson, 7th graders sort triangles according to various attributes such as acute, obtuse, isosceles, or equilateral. Students find the area and perimeter of triangles.
Lesson Plan
West Contra Costa Unified School District

Congruent and Similar Polygons

For Teachers 9th - 12th
What's similar about congruent and similar polygons? Young mathematicians first measure the side lengths and angles of given figures. They use these measurements to determine relationships between side lengths and angles of congruent and...