# Surf for More Math

## Lesson 1 - Comparing Positions on a Grid

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

**Goal**

Compare and order positive and negative numbers.

**Builds Upon**

Student Book pages 228-231

**Instructions for Use**

General
Co-ordinates Game helps students plot points on the coordinate
plane, and read the coordinates of a point plotted by the computer.

To use General Co-ordinates
Game, input the coordinates for X and Y to show the placement of the
house. Click the "Plot" button.

To obtain new coordinates for the house, click
the "New Point" button. Determine the X and Y coordinates
of the house. To check the coordinates, input them in the X and Y spaces
and click the "Check" button.

Gridblaster
prompts students to describe a location by identifying distances
from the intersecting axis.

To use Gridblaster, choose the level of difficulty
by moving the slider at the top of the screen, and click the "Start"
button.

Bugs burrow in the screen, as they travel towards the origin. Viruses
duplicate in numbers and fill the screen if they are not exterminated.
To destroy them and rack up points, plot their X and Y coordinates in
the control panel, and click the "Fire" button. As they move
about and fill the screen, the "Damaged Code Meter" fills with red. Once
it's completely filled, the game is over. When the bugs and viruses move
too close to the origin (0,0) they do more damage, but don't fire at the
origin.