EngageNY
Congruence, Proof, and Constructions
This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs. Each of the almost-forty lessons...
EngageNY
Construct an Equilateral Triangle (part 1)
Drawing circles isn't the only thing compasses are good for. In this first installment of a 36-part series, high schoolers learn how to draw equilateral triangles by investigating real-world situations, such as finding the location of a...
EngageNY
Construct a Square and a Nine-Point Circle
Anyone can draw a square, but can you CONSTRUCT a square? Here is a resource that challenges math scholars to create steps to finish their own construction. They test their ability to read and follow directions to complete a construction...
EngageNY
Rectangles Inscribed in Circles
Putting a rectangular object into a circular one—didn't the astronauts on Apollo 13 have to do something like this? Learners first construct the center of a circle using perpendiculars. They then discover how to inscribe a rectangle in a...
Curated OER
Constructing Quadrilaterals
High schoolers investigate quadrilateral construction in this geometry lesson plan. They use Cabri Jr. to construct the different quadrilaterals from the quadrilateral hierarchy given minimal definitions. The lesson plan reinforces the...
EngageNY
Construct an Equilateral Triangle (part 2)
Triangles, triangles, and more triangles! In this second installment of a 36-part series, your young mathematicians explore two increasingly challenging constructions, requiring them to develop a way to construct three triangles that...
EngageNY
Construct a Nine-Point Circle
There are an infinite number of points on a circle; can you find nine of them? After putting together a nine-point circle, pupils use constructions and their knowledge of triangle segments to determine the center of the circle. Learners...
EngageNY
Special Lines in Triangles (part 1)
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.
Mrs. Burgess
End of the Year Geometry Projects
Geometry students will be ecstatic about these engaging and enlightening end-of-the-year projects! Types of project ideas include interviewing a geometer, an ABCs of geometry poster, an engineering lab report, and origami work.
Texas Instruments
Traditional Copy an Angle - Compass Construction Using Cabri Jr.
Learnerss explore geometric construction in this geometry lesson. They will investigate the traditional construction for copying an angle using Cabri Jr. in lieu of paper and pencil construction. The lesson encourages students to explore...
EngageNY
Looking More Carefully at Parallel Lines
Can you prove it? Making assumptions in geometry is commonplace. This resource requires mathematicians to prove the parallel line postulate through constructions. Learners construct parallel lines with a 180-degree rotation and then...
Curated OER
Geometry and Shapes
High schoolers discuss and identify polygons and lines. In this geometry lesson, learners review liner, square and cubic units so they can incorporate it into the lesson on measurement and creating packing that are cost effective.
EngageNY
Characterize Points on a Perpendicular Bisector
Learn transformations through constructions! Pupils use perpendicular bisectors to understand the movement of a reflection and rotation. They discover that the perpendicular bisector(s) determine the line of reflection and the...
EngageNY
Unknown Angle Proofs—Proofs with Constructions
Provide your emerging mathematicians with the tools to learn as they incorporate auxiliary lines to solve unknown angle proofs in this continuing segment. They decipher information from a diagram to uncover the missing pieces and...
PBS
Plotting Pairs of Coordinate Points in All Four Quadrants to Construct Lines
Your young graphers are motivated by watching three Cyberchase videos to plot points in all four quadrants, connect pairs of points to make a line segment, and find the point of intersection of two lines.
CK-12 Foundation
Bisectors of Line Segments and Angles: Cut an Angle
Explore constructions through an interactive online lesson. Given an example of an angle bisector construction, learners investigate the markings to determine the method used. Challenge questions help solidify the steps.
Curated OER
Living in a Geometrical World
Students participate in a series of hand-on, online, and multimedia activities to examine 2 dimensional and 3 dimensional shapes. They describe common geometric solids. They construct rectangular prisms using straws and ribbon.
Curated OER
Get in Shape with Geometry
Using geoboards, computer programs, and hands-on manipulative materials, elementary schoolers engage in a study of two and three-dimensional geometric shapes. This lesson is chock full of good teaching ideas on the subject, and the...
Curated OER
Discovering Conic Sections in the Motion of Heavenly Bodies
Math scholars study conics and how they are used today. In this mathematical lesson, pupils construct and slice cones after viewing a demonstration.
EngageNY
Construct and Apply a Sequence of Rigid Motions
Breaking the rules is one thing, proving it is another! Learners expand on their previous understanding of congruence and apply a mathematical definition to transformations. They perform and identify a sequence of transformations and use...
EngageNY
Special Lines in Triangles (part 2)
Medians, midsegments, altitudes, oh my! Pupils study the properties of the median of a triangle, initially examining a proof utilizing midsegments to determine the length ratio of a median. They then use the information to find missing...
Curated OER
Shape Up!
An outstanding lesson on teaching the basic shapes and polygon names to young geometers is here for you. In it, learners investigate the role of basic polygons in the strength of structures. They use geoboards, rubber bands, streamed...
Jim Noble, Richard Wade & Oliver Bowles
Pyramid Model
Seeking to derive the formula for the volume of a square pyramid, geometry learners construct six square based pyramids that, when pieced together properly, form a cube. Two short videos demonstrate the relationship...
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...