Lesson Plan:


Day 1:

Warm-up Activity: (15 minutes)
Start by defining the words AREA and PERIMETER.

AREA- the number of square units needed to cover a surface enclosed by a geometric figure.
PERIMETER- the distance around a geometric figure.

To get the students thinking about different geometrical shapes give them an activity using dot paper. Ask the students to draw some shapes on the paper and attempt to find the area and perimeter of the shapes they have drawn.

Discussion: (40 minutes)
Geometrical and numerical representation of area and perimeter of polygonal shapes

Start the lesson by discussing what the student may have come up with on their own. Allowing the students to explain their reasoning behind their results.

Use the area and perimeter application from GSP Animation to Explore changes in area and perimeter of different shapes.

Using Geometer's Sketchpad draw some shapes (square, rectangle, triangle, trapezoid, and parallelogram, sketch provided in GSP Exercises) and discuss the area and perimeter of each by looking at the numerical value and “counting boxes” on the grid. Be sure to link the formulas for figuring out the area and perimeter to the actual geometric shape. For example, when you look at a triangle you can see and demonstrate very easily the fact that it is half of a square. Hence, this is the reason for using the formula ½ base x height.


Exercise: (10 minutes)
Draw and calculate the area and perimeter of several shapes using Geometer’s Sketchpad. This will allow the students to explore GSP and get familiar with it for tomorrow's lesson.


Wrap-up: (10 minutes)
As a “ticket out the door” they must summarize the day’s lesson and give an example of where this might be used. (For example, a construction worker would use this to build a house.) The purpose of this is to get them to put it in to words and relate it to a real-life situation in order to better remember the material.

Georgia Performance Standards Implemented:

NCTM Principles and Standards Implemented:



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