Illustrative Mathematics
Right Triangles Inscribed in Circles II
So many times the characteristics of triangles are presented as a vocabulary-type of lesson, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...
Curated OER
Perpendicular Lines
Students differentiate between parallel and perpendicular lines. In this geometry lesson, students identify the different angles created by perpendicular lines and parallel lines. They name the angles that are form when parallel lines...
Curated OER
Geometry: Lesson 1: Points, Lines, Segments, Angles
Fourth graders examine the concepts of, draw, and label points, lines, segments, and angles, They draw, label, and identify horizontal, vertical, intersecting, parallel, and perpendicular lines. They complete an associated worksheet that...
Curated OER
PRE ALGEBRA
Eighth graders find missing angles of triangles, quadrilaterals and angles formed by parallel lines cut by a transversal. They use area formulas to find the area of a figure; find the complement and supplement of a given angle; and know...
Curated OER
Pyramid Activity
Pupils explore the concept of pyramids. They determine if two sides of a pyramid are perpendicular using a graphing calculator, then discuss parallel and perpendicular lines and how to determine if two lines are parallel or...
Illustrative Mathematics
What Shape Am I?
Sharpen your pencil and grab a ruler, it's time to draw some quadrilaterals! Given the definition of a parallelogram, rectangle, and rhombus, learners draw examples and nonexamples of each figure. The three definitions are...
Curated OER
Corresponding Sides and Angles of Similar Triangles
Students differentiate between corresponding sides ad angles of two triangles. In this geometry lesson, students identify the differences as well as the similarities between two triangles. They differentiate between similar and...
Curated OER
Parallel-o-Home
Students investigate the usage of parallel and perpendicular shapes in the real world. For this geometry lesson, students investigate shapes for properties that are related to the real world. They relate all the properties of shape tot...
Curated OER
Around The Stop Sign
Students analyze a drawing of a regular octagon inscribed in a circle to determine angle measures, using knowledge of properties of regular polygons and the sums of angles in various polygons to help solve the problem. They use...
Curated OER
Find Someone Who........
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.
EngageNY
Rotations of 180 Degrees
What happens when rotating an image 180 degrees? The sixth lesson in the series of 18 takes a look at this question. Learners discover the pattern associated with 180-degree rotations. They then use transparency paper to perform the...
EngageNY
Definition of Reflection and Basic Properties
Discover the results of reflecting an image. Learners use transparency paper to manipulate an image using a reflection in this fourth lesson of 18. They finish by reflecting various images across both vertical and horizontal lines.
Curated OER
What's The Idea?
Sixth graders explore line segments, rays, parallel, perpendicular and intersecting lines. The teacher discusses, with the class, real life items that represent each geometric idea studied. They use cotton balls, strings and popsicle...
Ohio Department of Education
I Can Name that Angle in One Measure! - Grade Eight
Collaborative groups work with geometry manipulatives to investigate conjectures about angles. They create a graphic organizer to use in summarizing relationships among angles in intersecting, perpendicular and parallel lines cut by a...
Curated OER
Angle Pairs
Students identify different angle pairs. In this geometry lesson, students identify the different angles of two parallel lines cut by a transversal. They identify the interior and exterior angles.
Curated OER
Angles And Triangles
Seventh graders participate in a instructional activity that is focused upon the concepts of classifying different angles and triangles. They practice classifying triangles according to its kind that includes types of angles, congruence,...
Curated OER
Angle Action 1,2 and 3
Students investigate angles through construction. In this geometry lesson, students use a protractor to identify the measurement of an angle. They identify angles cut by a transversal and two parallel lines.
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...
Curated OER
Properties of Lines - Parallel and Perpendicular
Sixth graders identify parallel and perpendicular lines in the alphabet. In this line properties lesson, 6th graders use the letters of the alphabet to show parallel and perpendicular lines. Students open a Geogrid Mat on the computer...
Curated OER
Equations of Lines
Students classify lines, slopes and shapes. In this calculus lesson, students calculate the midpoint, segment and equation of a circle. They also review what a slope and angle of inclination is.
Curated OER
Plain Figures and Measuring Figures
Students investigate basic geometric concepts. For this geometry lesson, students explore solids through measuring and modeling. This assignment models the importance of understanding concrete objects in geometry.
Curated OER
IGD: Perpendicular Bisector
Students draw perpendicular bisectors. In this perpendicular bisectors instructional activity, students identify the perpendicular bisector in a polygon. They use web tools to create and measure perpendicular bisectors. ...
Curated OER
Geometry: Lesson 8
Eighth graders engage in a lesson that is concerned with the finding of angles that are found in different two dimensional figures. They compare and contrast exterior and interior angles while also determining the unknown measures of...
Curated OER
Right Triangles
Learners classify triangles and make connections regarding angle measurements and attributes of acute, right, and obtuse triangles. They listen to teacher define and explain triangles. Everyone imagines a place where a broken wing for a...