We are going to use the computers to learn about area and perimeter, but please do not turn your computers on or go to this page until I ask you to. I want to show you a little about the Shape Explorer applet first. Teacher Input You may choose to lead the students in a short discussion about how to find length, perimeter, and area for irregular figures. Explain to the students how to do the assignment. You should model or demonstrate it for the students, especially if they are not familiar with how to use our computer applets.
Perimeter is the total length around the object.
So imagine the grid lines are equal to one step. And imagine the outside edges of the figure are tight ropes. You want to see how many steps it will take you to get all the way around the edge. The number of steps would be the perimeter. Area is the amount of space in side the figure.