Perimeter Lesson Plan
Students will learn about perimeter and the units used to measure perimeter using
a variety of materials including their hands, feet, rulers, and computer applets.
Standards (NCTM 3-5)
Understand measurable attributes of objects and the units, systems, and processes
Apply appropriate techniques, tools, and formulas to determine measurements
- Understand such attributes as length, area, weight, volume, and size of angle
and select the appropriate type of unit for measuring each attribute
- Understand the need for measuring with standard units and become familiar
with standard units in the customary and metric systems.
- Develop strategies for estimating the perimeters, areas, and volumes of
- select and apply appropriate standard units and tools to measure length, area,
volume, weight, time, temperature, and the size of angles.
Students will need:
Students must be able to:
- perform basic mouse manipulations such as point,
click and drag.
- use a browser such as Netscape for experimenting with
- access to a browser
- pencil, graph paper, and rulers
- Focus and Review
Review any pertinent vocabulary.
Students will be able to demonstrate their knowledge of perimeter by calculating
the perimeter of computer generated shapes.
- Teacher Input
- Have the class measure the perimeter of their desk top using their
hands as the unit of measure. (Don't mention the word perimeter yet.)
- Discuss the different answers the students calculated.
- Discuss why the answers differed.
- Introduce the term perimeter.
- Have the students work in pairs and measure the perimeter of 4 or 5 different objects
around the room using different units: hands, feet, pencils, in, ft, etc.
- Monitor the students' progress.
- Have a couple of students share their examples.
- Discuss why it might be necessary to have a standard unit like: inches, feet, or
- Discuss why someone might need to know the perimeter of something.
(Example: fencing a yard)
- Demonstrate how to use the Perimeter Explorer.
(You may want to specify certain area settings.)
- Have the students answer a couple of computer generated problems with you.
- Demonstrate how to draw the figure generated by the computer on a piece of graph
- Have the students work either alone or in groups of two with the Perimeter Explorer.
- So you can check their progress, have the students copy the computer
generated figures on a piece of graph paper.
- Draw a grid on the board and draw a few shapes in the grid.
- Call on several different students to help you determine the perimeter
of each shape.
- Review the meaning of the word perimeter.
- Review the different units used to measure perimeter.