Published on Study.com, this lesson transcript was used in a professional development course for teachers.

1. How to Teach the Geometric Properties of Shapes
Lesson Transcript
When teaching the geometric properties of shapes, it is important to be as hands-on as possible. Students will
comprehend better with concrete examples.
Learning About Geometry
Whenever starting a new topic, it's a good idea to explain the ways it will directly relate to student's
lives. When it comes to geometry, there are many jobs that require at least basic geometric
knowledge such as builders, architects, interior designers, fashion designers, engineers, and many
others. Even if you're not in any of these careers, it's important to be able to communicate ideas that
may involve the use of geometric shapes.
Creating connections between ideas and words is crucial to developing understanding. When
teaching students the words, it's helpful to have them organized in a logical way. Consider guiding
the students through making a flipbook that they can use as a reference tool. Sorting the
vocabulary words will help the students make connections between the words, and drawing and
labeling shapes is extremely engaging and results in deeper learning. Remember to use these terms
consistently through all of your lessons. Here's an example of how information could be organized.
2-D Shapes
First, let's review 2-D shapes, also known as polygons. Polygons have height and width and sides,
vertices, and angles. They include the circle, triangle, quadrilateral, pentagon, hexagon, heptagon,
octagon, nonagon, and decagon, and they can be regular with equal sides and angles or irregular
with varied sides and angles.
All triangles have three sides, but there are many special types. Equilateral triangles have three
equal sides. Isosceles triangles have two equal sides. Scalene triangles have zero equal sides. Right
triangles have a 90-degree angle. Obtuse triangles have an angle that measures more than 90
degrees. Acute triangles have all angles measuring less than 90 degrees.
There are also many types of quadrilaterals, which have four sides. Here are some different kinds:

2. Parallelogram have two sets of parallel sides, and the opposite angles are equal
Trapezoids have one set of parallel lines
Rectangle have four right angles, and the opposite sides are equal
Rhombuses have four equal sides, and the opposite angles are equal
Squares have four equal sides, and four equal angles
3-D Shapes
Now let's review the properties of 3-D shapes. They have height, width, and depth and faces,
vertices, and edges. They include prisms, pyramids, cones, cylinders, and spheres.
Prisms have two polygonal faces and two parallelograms. Types of prisms include:
Triangular prisms
Rectangular prisms
Cubes
Pentagonal prisms
Hexagonal prisms
Pyramids have a polygonal face and a point. Think about the pyramids of Ancient Egypt. Types of
pyramids include:
Triangular pyramids
Square pyramids
Pentagonal pyramids
Curved shapes are what they sound like: geometric shapes with curves. Here are some common
curved shapes:
Cones have one circular face, curved edges, and one vertex
Cylinders have two circular faces, curved edges, and no vertex
Spheres have no faces, no edges, and no vertices
Using Manipulatives
There are many ways to make geometry hands-on. Students usually enjoy building with real-world
materials, such as toothpicks and marshmallows, or dry spaghetti noodles and clay. Materials like
these provide the opportunity to use vocabulary in a meaningful way.

3. For example, have students build a square, then have them push opposite vertices closer together
to make a rhombus. Ask questions that require students to communicate their observations and
discoveries. For example, what similarities and differences do you notice between a square and a
rhombus? Students will learn to use words like sides, vertices, and angles. They will notice they
need a word to explain the wider and narrower angles and the 90-degree angles.
After some exploration with flat shapes, students can start building and creating three-dimensional
shapes. This is a wonderful way to guide student discovery. Have students construct two congruent
triangles side-by-side, then have them transform one into a prism and the other into a pyramid. Ask
students to determine the number of faces, edges, and vertices for each one.
After giving students the opportunity to make some discoveries with the materials, have a post-
lesson discussion where you engage them in a discussion about the new vocabulary terms. Adding
a kinesthetic component like having students demonstrate kinds of angles with their hands and draw
them on paper with labels will solidify learning.
Incorporating Problem Solving
Manipulating pattern blocks is another way you can further geometric understanding. Give
students simple tasks like, ''How many ways can you find to make a hexagon?'' Problems can get
more advanced by incorporating area and perimeter. Using a triangle as a unit, give students
challenges like this word problem:
Sam is planning a garden. Sam wants to save money by spending as little as possible on fencing. The
garden must cover 25 units of land. What's the smallest amount of fencing Sam would need to protect the
garden from rabbits?
Another excellent method is using square shaped sticky notes and scissors. Students can quickly
learn how to decompose and compose shapes by completing simple tasks. Give students a
problem like, ''Find three different ways to cut the square in half, then rearrange the halves to make
as many new shapes as you can. Can you make a parallelogram, a triangle, a rectangle, and a
hexagon?''
3-D Shapes from 2-D Shapes
After showing students how to make various 2-D shapes from small pieces of paper, they can learn
to turn the 2-D shapes into 3-D shapes. Make tape, rulers, scissors, graph paper, and a circle
pattern or compass available. Give students the basics for making a few kinds of 3-D shapes. It's
not really necessary to figure out how to close all the shapes. You can talk about possible methods,
but the purpose is to get the concept. These are some ways to make different shapes:
Cylinder: Curl the sides of a rectangle together and tape.

4. Cone: Find the center of a circle by folding it twice. Draw two lines from the center to the edge and cut out a
piece of the pie, then bring the edges together.
Rectangular prism: Fold a rectangle in half two times so you have four rectangles in a row. Bring the two
edges of the paper together and tape.
Triangular prism: Fold a rectangle in half two times so you have four rectangles in a row. Bring the two
edges of the paper together and put one edge under the other and tape.
Triangular pyramid: Fold a square in half twice from the corners to make four triangles. Cut a line from one
corner to the middle point. Bring the two triangles next to the cut together so they overlap and tape.
Kids will be motivated if you allow them to make a connection to art and create a sculpture or
connect to social studies and create a village.
Lesson Summary
Geometry provides many opportunities to give students hands-on, concrete experiences. It's
important to record this hands-on learning in a logical way to increase retention of the material. You
can start by making a flipbook of common 2-D and 3-D shapes. It's always helpful to give students
opportunities to write and draw about their learning. Using manipulatives, like real-world building
materials, pattern blocks, and sticky notes can all help students learn about geometry by actually
creating shapes. You can incorporate tasks and problem solving into these projects to challenge
their learning.