Download Lesson Title:Reading Graphs for Information

MCS Lesson of the Week
Lesson Title: Oh My Polygon!
Grade: 6
Strand: Geometry and Spatial Sense
Learning Goal (Curriculum Expectations)
Gr. 6 – classify and construct polygons and angles
Reasoning and Proving – develop and apply reasoning skills to make and investigate conjectures and construct and defend
arguments
Representing – develop and apply reasoning skills to make and investigate conjectures and construct and defend arguments
Key Ideas
- Geometric objects have properties that allow them to be classified and described in a variety of different ways
- Understanding relationships between geometric objects allow us to create any geometric object by composing and
decomposing other geometric objects
ICT Standards:
Lesson Components
Part 1: Minds On
 What do we know about:
Right angles
Acute angles
Obtuse angles
Straight angles
Reflex angles?
Students use the Notebook Angle
Types Flash file to describe the
different angles using attributes and
geometric properties
Anticipated Student Responses




Opportunities for ICT Integration
compare to benchmark angles
o smaller than a right angle
provide measurement ranges
o between 0º and 89º
compare to other types of angles
o smaller than an obtuse angle
describe the arms in comparison to other
angles
o the arms would be closer together
than those of a 90º angle

Use Notebook Flash file to
investigate angles and
record findings

students could project their
notes
Part 2: Action
Problem:
Construct a polygon that has:
o 3 different types of angles
o at least 1 side with a length of 3 units

Use PhotoBooth to share Geoboard or
grid paper solutions
Name and describe your polygon using geometric properties including
lines of symmetry.
Students work independently, in pairs, or small groups.
Possible materials: Geoboards, grid paper, GSP, Smart Notebook
IT Services: Teaching and Learning with Technology
- Winter 2011 - http://community.elearningontario.ca
MCS Lesson of the Week
Part 3: Consolidation
With the students, sort polygons according to the number of lines of symmetry.
Generalize:
When does a polygon have zero lines of symmetry? Only one line of symmetry?
What types of polygons have more lines of symmetry?
Consider the number of sides, lengths of sides, angles.
Part 3: Highlights and Summary
Polygons can be described and sorted according to:
o number of sides
o length of sides
o types of angles
o lines of symmetry
There are different ways of finding lines of symmetry.
The more sides a regular polygon has, the more lines of symmetry there will be.
The number of lines of symmetry in a regular polygon is always equal to the number of vertices.
Part 3: Practice
How many lines of symmetry can a pentagon with 2 right angles have?
Can a pentagon have more lines of symmetry?
Explain and justify your solution.
IT Services: Teaching and Learning with Technology
- Winter 2011 - http://community.elearningontario.ca