Mathematics 4

# Lesson 5 - Perimeter of Rectangles

To encourage students to have fun on the Web while learning about Perimeter of Rectangles, here are some games and interactive activities they can do on their own or in pairs.

### Goal

Use the length and width of a rectangle to find its perimeter.

### Builds Upon

Student Book pages 134-135

### Instructions for Use

Geoboard lets students investigate perimeters of rectangles.

To use Geoboard, select a circle by holding the mouse button down, and drag it to any location on the gird. Release the circle to anchor it. A red node appears at the top of the circle. Click on any part of the circle and drag it in any direction. It will stretch much like a rubber band. Secure the band to any points on the grid to make rectangles.

Click on the circle again to add other bands. To colour the rectangle, click first on it and then on the colour buttons to the left. To release a node, hold the Ctrl key down and click on the node. Click on the 'Measure' button to determine the perimeter of the rectangle. Click on the 'Clear' button to start the exercise over again.

Box Perimeter allows students to investigate perimeters of rectangles.

To use Box Perimeter, drag boxes from the left inside of the window to the workspace and count the edges of each box that are not touching another box. Press the "Show Perimeter" button to check your answer with the computers.

To delete a box drag it off of the screen.