Format Factory - Convert Anything

Much like CD Burner XP below this is a totally free no strings attached piece of software that simply does what is says.  It converts multitudes of audio and video files from one format to another.  Check out the site for all the finer details of exact formats and procedures but I have been using this over a year now and have had no rejections on file formats.  Another must install on your school PC's.

Get it here