Scratch

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1. Open Scratch if it isn't already open.
2. Shift-Click the R in the logo of Scratch, in the top left-hand corner. Select "turn fill screen off".
3. Click the white space at the bottom of the window. This menu is called the World Menu.
4. Follow this path: appearance.../set desktop color....
Click a color to change the white space a different color and then close out of the color changer.
5. To save your change, Shift-click the R in the logo again. When it asks you, " Close non-Scratch windows and save this image in end user (fillScreen) mode?", click yes. Scratch should close. Open Scratch again and repeat step 2. the white space is now a different color!