EngageNY
How Do 3D Printers Work?
If we stack up all the cross sections of a figure, does it create the figure? Pupils make the connection between the complete set of cross sections and the solid. They then view videos in order to see how 3D printers use Cavalerie's...
EngageNY
Triangle Congruency Proofs (part 1)
Can they put it all together? Ninth graders apply what they know about proofs and triangle congruence to complete these proofs. These proofs go beyond the basic triangle congruence proofs and use various properties, theorems, and...
EngageNY
Thales’ Theorem
Isn't paper pushing supposed to be boring? Learners attempt a paper-pushing puzzle to develop ideas about angles inscribed on a diameter of a circle. Learners then formalize Thales' theorem and use geometric properties to develop a proof...
EngageNY
The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar
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...
EngageNY
General Pyramids and Cones and Their Cross-Sections
Are pyramids and cones similar in definition to prisms and cylinders? By examining the definitions, pupils determine that pyramids and cones are subsets of general cones. Working in groups, they continue to investigate the relationships...
EngageNY
Analytic Proofs of Theorems Previously Proved by Synthetic Means
Prove theorems through an analysis. Learners find the midpoint of each side of a triangle, draw the medians, and find the centroid. They then examine the location of the centroid on each median discovering there is a 1:2 relationship....
Curated OER
Congruent Polygons: Copying Stretchy Shapes
Third graders investigate congruent polygons through dance. In this congruency lesson, 3rd graders do the "brain dance" as a warm up. They review polygon names by singing "The Polygon Chant," before mirroring congruent shapes with a...
Curated OER
Area of Tangram Pieces
Mathematicians calculate the area of a tangram piece without using formulas. They use a geometry journal to record activities during this lesson. They make a set of tangrams and use them to compute area. They use...
Curated OER
Word Problems: Geometry
Students solve word problems by using basic geometry. In this geometry lesson, students use geometric formulas to find the perimeter, area, and volume of objects. Students complete a worksheet.
PBS
Arguing over Area
With the help of the Area Officers and Perimeter Patrol, you learners will develop a better understanding of area and its relationship to perimeter. First, they view a video clip from Cyberchase, and then they visit a website to...
Curated OER
Branding Circles, Squares, Rectangles, Triangles
Compare and classify 2-D shapes! Kindergarteners inspect the attributes of plane shapes and examine shapes in everyday life. They label the circles, squares, rectangles, and triangles they find. This is the website where you can find the...
Curated OER
Mining Shapes
For this 2-D shapes lesson, kindergarteners review plane shapes attributes. They engage in a shape hunt in the classroom and create art using plane shapes. A good, hands-on lesson!
Arizona State University
Tricorn Triangles
Help your learners examine triangles. Pupils explore the different sizes and measurements of triangles. They discover triangles can be isosceles or scalene, and examine the attributes of triangles. Here is the website where you can...
Curated OER
Sphere Dressing
Geometric design makes a fashion statement! Challenge learners to design a hat to fit a Styrofoam model. Specifications are clear and pupils use concepts related to three-dimensional objects including volume of irregular shapes and...
Curated OER
Poly-Mania
This hands-on lesson takes young geometers on a tour of 2D polygons and 3D polyhedrons. After exploring different web resources and discussing geometric shapes, small groups construct models of polyhedrons using bendable straws. Note:...
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
"A Slice of the Cone"
Here is a set of lessons that explore conics in a number of different ways. Starting with modeling how a conic is produced by the way a plane cuts the cone, to solving complex word problems, algebra learners progress through a series of...
American Statistical Association
Exploring Geometric Probabilities with Buffon’s Coin Problem
Scholars create and perform experiments attempting to answer Buffon's Coin problem. They discover the relationships between geometry and probability, empirical and theoretical probabilities, and area of a circle and square.
Project Maths
Planes and Points
Build a solid foundation on which to develop future concepts. Through a guided exploration, learners compare and contrast the characteristics of points, lines, planes, rays, and segments. They measure lengths and practice notation for...
Project Maths
Introduction to Trigonometry
The topic of trigonometric ratios is often covered with loads of rote memorization baked into the activity. This activity set, however, leans more on using similar triangles and discovery learning to help young geometers develop a deeper...
Curated OER
Marshmallow Figures
Learners enjoy making 3-D figures while learning about rectangular prisms, pyramids, vertices, edges, and faces. After a lecture/demo, students use marshmallows, toothpicks and a worksheet imbedded in this lesson to create 3 dimensional...
Curated OER
Fun with Shapes
Young mathematicians identify shapes and their correct names. They work with partners using various manipulatives and computer software to reinforce the concept. I really like these lesson plans. They are well-designed, the procedures...
Improving Measurement and Geometry in Elementary Schools
Rep Tiles
In addition to the catchy title, this lesson plan provides upper graders an opportunity to more closely scrutinize the attributes of plane figures. In particular, they focus on the similarity of different shapes. Both whole-class and...
Alabama Learning Exchange
"I Saw the Sine"
Discover trigonometric ratios that complement each other. Using two videos, the lesson introduces the trigonometric ratios. The class discovers the relationship between the sine and cosine of complementary angles.