5.G.4
2011
Domain: Geometry
Cluster: Classify two-dimensional figures into categories based on their properties.
Standards: 4. Classify two-dimensional figures in a hierarchy based on properties.
Essential Questions



How can angles be
measured and
classified?

How can polygons,
triangles, and
quadrilaterals be
described,
classified, and
named?
Content Statements

Enduring Understandings
Students will
classify and
analyze twodimensional
figures based on a
hierarchy of
properties.
Assessments
Polygons can be
described and classified
by their sides and angles.
Classify two-dimensional
shapes into categories
based on their properties.
Activities, Investigation, and Student Experiences
1. Regular/Irregular Hierarchy Diagram
Materials: Rulers
a. Create a Hierarchy Diagram using the following
terms: Polygons, Regular Polygons, Irregular
Polygon, Triangle, Quadrilateral, Pentagon,
Hexagon, Octagon
b. Draw one or more examples under each category on
your diagram.
c. Explain your reasoning using mathematical
language.
2. Students can use graphic organizers such as flow charts
or T-charts to compare and contrast the attributes of
geometric figures. Have students create a T-chart with a
shape on each side. Have them list attributes of the
shapes, such as number of sides, number of angles, type
of lines, etc. they need to determine what is alike or
different about the two shapes to get a larger
5.G.4

What properties may help to classify a figure?
Properties of sides—parallel, perpendicular,
congruent, number of sides.
Properties of angles—types of angles,
congruent
Examples:
A right triangle can be both scalene and isosceles, but
not equilateral.
A scalene triangle can be right, acute and obtuse.

What are the ways of classifying triangles?
Angles
Right: The triangle has one angle that
measures 90º.
Acute: The triangle has exactly three angles
that measure between 0º and 90º.
Obtuse: The triangle has exactly one angle that
measures greater than 90º and less than 180º.
Sides
Equilateral: All sides of the triangle are the
same length.
Isosceles: At least two sides of the triangle are
the same length.
Scalene: No sides of the triangle are the same
length.
2011
classification of the shapes. Pose questions such as,
“Why is a square always a rectangle?” and “Why is a
rectangle not always a square?”
3. Create a hierarchy diagram using the following terms:
a. Polygon, Quadrilateral, Rectangle, Rhombus, and
Square
Polygon
↓
Quadrilateral
↙
↘
Rectangle
Rhombus
↘
↙
Square
5.G.4
Equipment Needed:
Student whiteboards
Teacher Resources:

http://coedpages.uncc.edu/abpolly/math/core/unpacki
ng/unpacked-5th.pdf

http://illuminations.nctm.org/ActivityDetail.aspx?ID=
21

http://illuminations.nctm.org/ActivityDetail.aspx?ID=
35

www.graphic.org/class.html
Calculators
Internet
Smartboard
Manipulatives
Overhead
Protractor
2011