1. Describe & Analyze Two-Dimensional Shapes
Teacher Quality Grant
Describe & Analyze Two-Dimensional Shapes
Polygons

2. Introduction to Polygons
What are POLYGONS?
Polygons are closed figures made up of straight lines.
The goal is for participants to:
precisely describe, classify, and understand relationships among types of two-dimensional objects using their defining properties
use Venn Diagrams to sort polygons according to certain attribute
Start be asking participants “What are polygons?” Expected answers would be closed 2-D shapes made up straight lines. They may give you names of polygons. Record most answers on the board. .

3. Introduction to Polygons.
Polygon
Image
Definition
Triangle
Quadrilateral
Pentagon
Ask participants to make a 3-page((12 sides) foldable booklet. Number pages C (cover), then 1, 2, 3, thru 11. This should take no more than 5-minutes.
Starting with page 2, ask them to make a chart like the one on the screen. Ask them to illustrate/draw a picture of the meaning of the word, then write a definition (in their own words). Give them 5 minutes !

4. Introduction to Polygons.
Polygon
Image
Definition
Hexagon
Octagon
Decagon
On page 3, ask them to make a chart like the one on the screen. Ask them to illustrate/draw a picture of the meaning of the word, then write a definition (in their own words). Give them 4 minutes !

5. Introduction to Polygons.
Polygon
Image
Definition
Regular Polygon
Irregular polygon
Congruent Polygons
On page 4, ask them to make a chart like the one on the screen. Ask them to illustrate/draw a picture of the meaning of the word, then write a definition (in their own words). Give them 3 minutes !
Now put them in groups of three. Give each group a sheet of chart paper, markers. Each group will first, examine each persons definitions and illustrations, then use the chart paper to write the 9 vocabulary words, an illustration of the word and definition.
Have each group tape their chart paper to the wall/board.

6. Introduction to Polygons
Image
Definition
Triangle
A three-sided polygon.
Quadrilateral
A four-sided polygon.
Pentagon
A five-sided polygon.
Ask the participants to look over all charts. Do they see any definitions that are different from theirs? Talk about each polygon. Have them look at each word and see if they can determine the meaning of the word. Talk about Etymology of each word.
TRIANGLE: Latin from tri- "three" and angulus "corner, angle.”
QUADRILATERAL: Latin from quadri- "four" and latus (or lateris) "side”
PENTAGON: Greek from pente "five" + gonia "angle"

7. Introduction to Polygons
Image
Definition
Hexagon
A six-sided polygon.
Octagon
An eight-sided polygon.
Decagon
A ten-sided polygon.
Ask the participants to look over all charts. Do they see any definitions that are different from theirs? Talk about each polygon. Have them look at each word and see if they can determine the meaning of the word. Talk about Etymology of each word.
HEXAGON: Greek from hex "six" and gonia "angle"
OCTAGON: Greek from okto "eight” and + gonia "angle,"
DECAGON: Greek from eka "ten" and gonia "corner, angle"

8. Introduction to Polygons
Image
Definition
Regular Polygon
A regular polygon is a polygon which is equiangular (all angles are equal in measure) and equilateral (all sides have the same length).
Irregular polygon
An irregular polygon is any polygon that is not a regular polygon. It can have sides of any length and each interior angle can be any measure
Congruent Polygons
Two polygons that are equal in shape and size.
Ask the participants to look over all charts. Do they see any definitions that are different from theirs? Talk about each polygon. Have them look at each word and see if they can determine the meaning of the word. Talk about Etymology of each word.
POLYGON: Greek from polys "many" and gonia "angle"

9. Introduction to Polygons
Concave Polygons can be cut by a straight lines in more than two points
Convex Polygons can be cut by any straight line in at most two points
Polygons can be convex or concave. Although the Elementary FCAT does not TEST concave and convex, it is important for participants (and their students) to understand the concave and convex.
Open this site from the PowerPoint. Ask each participant to go to this web site
Have then ‘play’ with the page. Ask them to make conjectures about regular and irregular polygons as it relates to concave and convex. Give them a few minutes to play.
Ask them what they discovered. Some things they may say:
Regular shapes can ONLY be convex (not concave)
Irregular shapes can be either convex, or concave.
If an irregular shape is made to cross over itself, it is neither convex or concave.
Concave has a depression in the picture.
Regular polygons have all sides equal.
Regular polygons have all angles equal.
Irregular polygons have sides with different lengths.
Irregular polygons have angles with different measurements. .
Concave
Convex

10. Apple Race
For the Apple Race have participants stay in the groups (of three). Each group needs one Apple Race sheet and a bag of pattern blocks (Hexagons, Triangles, Trapezoids, and Parallelograms). Each person takes 12 pattern blocks – they can be given out one at a time.
Rules:
Determine who is first (second, last)
Each person places one of the pattern block on the Apple Race grid.
The object is to take turns placing one pattern piece at a time until the apple is covered or you can no longer move. The person placing the last piece is the winner!
Variation: The person placing the last piece loses the game.

11. Special Triangles Right Equilateral Isosceles Scalene Triangle Image
Definition
Right
Equilateral
Isosceles
Scalene
Starting with page 6 in their foldable booklet, ask them to make a chart like the one on the screen. Ask them to illustrate/draw a picture of the meaning of the word, then write a definition (in their own words). Give them 5 minutes !.
Now put them in groups of three. Give each group a sheet of chart paper, markers. Each group will first, examine each persons definitions and illustrations, then use the chart paper to write the 9 vocabulary words, an illustration of the word and definition.
Have each group tape their chart paper to the wall/board.

12. Special Triangles Right Equilateral Isosceles Scalene Triangle Image
Definition
Right
A triangle with one right angle.
Equilateral
A triangle with three congruent sides.
Isosceles
A triangle with two congruent sides and two congruent angles.
Scalene
A triangle having no congruent sides.
Ask the participants to look over all charts. Do they see any definitions that are different from theirs? Talk about each special triangle. Have them look at each word and see if they can determine the meaning of the word.

13. Special Quadrilaterals
Triangle
Image
Definition
Square
Rectangle
Parallelogram
Trapezoid
Rhombus
Starting with page 7, ask them to make a chart like the one on the screen. Ask them to illustrate/draw a picture of the meaning of the word, then write a definition (in their own words). Give them 5 minutes !.
Now put them in groups of three. Give each group a sheet of chart paper, markers. Each group will first, examine each persons definitions and illustrations, then use the chart paper to write the 9 vocabulary words, an illustration of the word and definition.
Have each group tape their chart paper to the wall/board.

14. Special Quadrilaterals
Triangle
Image
Definition
Square
A rectangle with four congruent sides; also, a rhombus with four right angles.
Rectangle
A parallelogram with four right angles.
Parallelogram
A quadrilateral in which both pairs of opposite sides are parallel.
Trapezoid
A quadrilateral with exactly one pair of parallel sides.
Rhombus
A parallelogram with four congruent sides.
Starting with page 7, ask them to make a chart like the one on the screen. Ask them to illustrate/draw a picture of the meaning of the word, then write a definition (in their own words). Give them 5 minutes !. .

15. Quadrilateral Family Tree
Square
Rectangle
Parallelogram
Rhombus
Trapezoid
Square
Square
Rectangle
Rhombus
Square
Ask participants to place polygon shapes within each column… A shape can be in multiple columns. For example, a square fits in the rectangle column because a rectangle is defined as having opposite equal and 4 right angles. A square has these qualities.
Square 
Rectabgle  square
Parallelogram  square, rectangle, rhombus
Rhombus  square
Trapezoid 

16. Tangram Activity
Tasks: Cut your own tangram set by following directions on the Activity sheet.
With partners make a list of all the mathematical terms you could illustrate using your tangrams.
a. Using only the four pieces in figures e and f , how many different shapes can you make?
b. Using all 7 pieces, how many different quadrilaterals can you make?