With XNA Game Studio, included as part of the Windows Phone Developer tools, you can create games for Windows, Xbox 360, and Windows Phone 7. Jump in and play with free tools, learn from our extensive samples and tutorials libraries, then get your game on Xbox LIVE Indie Games and the Windows Phone 7 Marketplace. If you're ready to go professional, Xbox LIVE programs are available for both platforms.

Find more here

http://create.msdn.com/en-in/education/gamedevelopment