Squeak Etoys is a "media authoring tool"-- software that you can download to your computer
and then use to create your own media. You can write out your project and share it with others.
Etoys runs on any Mac or Windows machine, as well as on the OLPC XO machine.
It is free.
Find out about Etoys.
Text of this guide (for searching): Menu: Playfield Graph Paper Options
Use a standard 16x16 graph paper on a Playfield or make one with custom sizes and colors. Choose playfield options and keep that menu open too.
The second menu's list includes two choices:
use standard texture
make graph paper. Click on a Playfield in Supplies; then right click to open its halo handles.
Click on its menu. Click the menu's push pin to keep it open. If you choose make graph paper, a dialog box asks: Enter grid size. This example's grid size is 64.
New dialog boxes will open that allow you to assign background and line color. Click the green clock to run the script
that draws a graph on this grid.