One of my students has put a picture from the Internet on my desktop. How do I get it back to the regular desktop?

This is a common problem for classroom teachers but it is easily remedied so do not panic.
• Go to Start on the task bar.
• Select Settings, Control Panel.
• The Control Panel window will open. Double click on the Display icon.
• The Display Properties window will open (Background Tab should be active in the window).
• Select None in the Wallpaper window, Click the Apply button
• Click the OK button.
• You may want to adopt a “No Download” policy to avoid this
in the future. This could cause a virus problem on your system
(Nimbda can spread from Internet web sites).
Another method of accessing the Display Properties:
• Right click on the desktop, select Properties from the pop-up
menu.
• Follow the steps above once the Display Properties window opens