powerpoint background?

Try stock.xchng - it's a free stock photo site.

Yeah, there's some junk on there, but a lot of it is really nice and it's mostly high enough resolution for a PowerPoint background (it shows the size of the file on the regular search view).

And be careful with the licensing notes - each picture has its own information. No one is looking for money, but they sometimes ask for you to get permission or notify them of use. If it is available to download (some of them are locked out until you get permission), you should be able to use it in a classroom or small internal business meeting without a problem.

http://www.sxc.hu/index.phtml

Power point is good source of showing creativity. If you want to change your background in power point, then at first you have to find out the best or your desired background and have to save it on your computer. Then follow the rules of power point and change it. Go to the slide bar and right click and change the background. Visit the source link to learn more.