## Wednesday, February 6, 2008

### What's the Point?

Typically, students love to do coordinate grid problems. Perhaps it is because they do not perceive it as having much to do with math. Perhaps it is because it reminds them of the game Battleship. There is, however, a lot of terminology associated with the grids. I always stress that students try to use the correct vocabulary and talk like mathematicians. Here is a quick run down of the vocabulary you will need to know:

A coordinate grid is just one way to show relationships between numbers. The grid has two axes. The horizontal axis (side to side) is called the x-axis. The vertical axis (up and down) is called the y-axis. The place where the x-axis and the y-axis come together is called the point of origin.

To find a coordinate, you must first identify the object’s location on the grid. The location is listed as (x,y) with the x coordinate always listed first, then the y coordinate. This is called an ordered pair and is written in parenthesis.

In second grade (thankfully) we only use the first quadrant (the upper right corner of the coordinate grid). We do discuss negative numbers and work with them a little in second grade, but students generally are not ready to move into other coordinates yet.

Let’s take a look at a sample coordinate grid below.

There are many games online that use all quadrants, so I have fished trough to find the games that use only the first quadrant for practice.

What's the Point? Play level "easy" only.
Where is Hurkle?
Find the Target
Fly Games These games can be printed and played anywhere. (They are great "car games" to play on the go.)